ОПТИЧЕСКИЙ НОСИТЕЛЬ ЗАПИСИ И УСТРОЙСТВО ЗАПИСИ/ВОСПРОИЗВЕДЕНИЯ

Предложен оптический носитель записи. Он включает в себя специально выделенную область, в которой записана информация, касающаяся дефекта, соответствующего дефектному блоку в области пользовательских данных. При этом информация, касающаяся дефекта, включает в себя запись списка последовательных дефектов, включающего в себя информацию, касающуюся дефектов, размещенных в последовательных местоположениях области пользовательских данных. Также предложено устройство для использования этого оптического носителя записи. 3 н.п. ф-лы, 12 ил.

НЕПЕРЕЗАПИСЫВАЕМЫЙ ОПТИЧЕСКИЙ ДИСК И СПОСОБ И УСТРОЙСТВО ДЛЯ ВОССТАНОВЛЕНИЯ УПРАВЛЯЮЩЕЙ ИНФОРМАЦИИ ДИСКА С НЕПЕРЕЗАПИСЫВАЕМОГО ОПТИЧЕСКОГО ДИСКА

Предлагаются неперезаписываемый оптический носитель записи и способ и устройство для хранения и восстановления информации управления дефектами для него. Носитель записи включает в себя, по крайней мере, один записывающий слой и область данных на записывающем слое. Область данных включает, по крайней мере, одну резервную область и область пользовательских данных. Резервная область содержит, по крайней мере, один кластер замещения, а каждый кластер замещения хранит в себе адресную информацию соответствующего дефектного кластера. Техническим результатом является снижение появления ошибок, вызванных потерей управляющей информации. 3 н. и 17 з.п. ф-лы, 11 ил.

НОСИТЕЛЬ ИНФОРМАЦИИ И УСТРОЙСТВО ДЛЯ ЗАПИСИ И/ИЛИ ВОСПРОИЗВЕДЕНИЯ ДАННЫХ

Носитель информации содержит, по меньшей мере, два слоя хранения информации, каждый из которых включает в себя область регулирования оптимальной мощности для получения состояния оптической записи. Области регулирования оптимальной мощности в соседних слоях из слоев хранения информации размещены на различных радиусах носителя информации. Одна или более буферная область размещена на обеих сторонах каждой из областей регулирования оптимальной мощности. Область только для воспроизведения размещена в одном из слоев хранения информации так, что она находится напротив области регулирования оптимальной мощности соседнего одного из слоев хранения информации и по меньшей мере одной буферной области, размещенной на одной стороне соответствующей области регулирования оптимальной мощности. Технический результат - улучшение качества записи носителя информации. 5 н.п. ф-лы, 18 ил., 1 табл.

УСТРОЙСТВО И СПОСОБ ДЛЯ ЗАПИСИ ЦИФРОВОГО ИНФОРМАЦИОННОГО СИГНАЛА И НОСИТЕЛЬ ЗАПИСИ

Изобретение относится к записи цифрового информационного сигнала и подкодового сигнала в наклонных дорожках на носителе записи. Устройство содержит средства ввода цифрового информационного сигнала и подкодового сигнала, средства форматирования для размещения частей информации подкодового сигнала в блоках подкодового сигнала и для размещения частей информации информационного сигнала в блоках информационного сигнала и для объединения блоков подкодового сигнала и блоков информационного сигнала в полный телевизионный сигнал. Множество блоков 2m подкодового сигнала записывается в часть дорожки для записи подкодового сигнала. Множество блоков информационного сигнала записывается в часть дорожки для записи информационного сигнала. Имеются средства для генерирования сигнала кода времени и для размещения сигналов кода времени в определенных блоках подкодового сигнала, приспособленные для генерирования сигналов кода времени для размещения в определенных блоках подкодового сигнала в части записи подкодового ...

ИНФОРМАЦИОННЫЙ НОСИТЕЛЬ ДАННЫХ И СПОСОБ ЗАПИСИ ДАННЫХ НА НЕГО

Информационный носитель данных включаем в себя несколько слоев записи. Каждый из них имеет область данных пользователя, на которую данные могут быть записаны головкой записи/считывания. Данные записывают в порядке слоев записи от самого ближнего до самого дальнего от головки записи/считывания. Записываемая область в области данных пользователя каждого последующего слоя в направлении удаления от головки записи/считывания уменьшается по сравнения с предыдущим слоем. При этом каждый слой записи содержит записываемую область в области данных пользователя и область оптимального регулирования мощности (ОРС), чтобы поддерживать одни и те же характеристики записи/воспроизведения между множеством слоев записи. 2 н. и 5 з.п. ф-лы, 2 табл.,8 ил.

НОСИТЕЛЬ ЗАПИСИ, ИМЕЮЩИЙ СТРУКТУРУ ДАННЫХ ДЛЯ УПРАВЛЕНИЯ, ПО КРАЙНЕЙ МЕРЕ, ОБЛАСТЬЮ ДАННЫХ НОСИТЕЛЯ ЗАПИСИ, И СПОСОБЫ И УСТРОЙСТВА ЗАПИСИ И ВОСПРОИЗВЕДЕНИЯ

Структура данных на носителе записи включает временную зону управления дефектами, в которой хранится блок данных. Блок данных включает информацию о записи и временную информацию о состоянии носителя записи. Информация о записи предоставляет информацию о зонах непрерывной записи в области данных носителя записи. Временная информация о состоянии носителя записи предоставляет информацию о состоянии носителя записи и содержит, по крайней мере, один указатель информации во временной зоне управления дефектами. Технический результат: оптимизация управления дефектами при помощи информации о состоянии носителя записи. 5 н. и 26 з.п. ф-лы, 6 ил.

УСТРОЙСТВО ЗАПИСИ ДАННЫХ НА ДИСК ДЛЯ ОДНОКРАТНОЙ ЗАПИСИ И ДИСК ДЛЯ ОДНОКРАТНОЙ ЗАПИСИ

Предложены диск для однократной записи и устройство записи данных. Носитель включает область информации доступа (AIA), в которой записана информация относительно местоположения TDMA, в которой окончательно записана обновленная предопределенная информация. Информация относительно местоположения TDMA, в которой окончательно записана обновленная предопределенная информация, является временной структурой дефектов диска (TDDS). Техническим результатом является сокращение времени доступа для считывания обновленной информации. 2 н.п. ф-лы, 12 ил.

СПОСОБ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ НА НОСИТЕЛЕ И УСТРОЙСТВО ДЛЯ ВОСПРОИЗВЕДЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ С НОСИТЕЛЯ ЗАПИСИ

Использование: изобретение относится к накопителю для записи цифровых данных на многодорожечную запоминающую среду. Сущность изобретения: с целью повышения точности и помехозащищенности записи и воспроизведения цифровой информации устройство содержит блок воспроизведения и демодуляции, декодирующий блок с обнаружением и коррекцией ошибок, блок звукового воспроизведения, при этом декодирующий блок выполнен в виде двух счетных блоков, двух декодеров, многосегментного запоминающего устройства с произвольной выборкой (ЗУПВ), двух блоков доступа к этому ЗУПВ. 2 с. и 7 з.п. ф-лы, 8 ил.

УСТРОЙСТВО ДЛЯ ЗАПИСИ И/ИЛИ ВОСПРОИЗВЕДЕНИЯ ДАННЫХ В ОТНОШЕНИИ НОСИТЕЛЯ ЗАПИСИ С ОДНОКРАТНОЙ ЗАПИСЬЮ И ЗАПИСЫВАЮЩАЯ СРЕДА С ОДНОКРАТНОЙ ЗАПИСЬЮ

Заявлены устройство для записи и/или воспроизведения временного списка дефектов и носитель записи с однократной записью. Устройство обеспечивает проверку после записи временной области информации о дефекте. Если в кластере этой области, содержащем информацию о дефекте, имеется дефект, то устройство воспроизведения записывает соответствующий блок информации в следующий свободный кластер временной области управления дефектами. При этом устройство записывает во временную область управления дефектами информацию, указывающую положение кластера с информацией о дефекте. 5 н. и 15 з.п. ф-лы, 9 ил.

СПОСОБ АДАПТИВНОЙ АНАЛОГОВОЙ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ

Способ основан на образовании из двоичных сигналов информационных кодовых групп и распределении их парами по блокам одинаковой протяженности, зависящей от установленного значения протяженности дефектов носителя. Каждый блок дополнен служебными маркерными и контрольными парами кодовых групп. Формируют последовательности дополненных блоков пар кодовых групп, которые разбивают на подпоследовательности, каждая из которых включает служебные маркерные и адресные пары кодовых групп и заданные числа информационных и дополнительно сформированных контрольных пар блоков. Формируют сигнал записи каждой подпоследовательности блоков в виде последовательности установленного числа маркерных и адресных отрезков синусоидального сигнала с установленными максимальными и минимальными значениями экстремумов амплитуды и порядком чередования адресных отрезков в зависимости от значений кодов номеров текущей подпоследовательности. Подпоследовательности с искаженным блоком и искаженного блока, а также информационных ...

СПОСОБ АДАПТИВНОЙ ШИРОТНО-ИМПУЛЬСНОЙ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ НА МАГНИТНЫЙ ИЛИ ОПТИЧЕСКИЙ НОСИТЕЛЬ

Способ адаптивной широтно-импульсной записи цифровой информации на магнитный или оптический носитель, включающий распределение двоичных сигналов входной информационной последовательности по кодовым группам и кодовых групп по блокам, формирование информационных перепадов сигналов записи блоков кодовых групп по двум уровням и временных интервалов между перепадами в соответствии с кодовыми группами и их значениями, формирование маркерных перепадов сигналов записи блоков кодовых групп по двум уровням и соответствующих перепадам временных интервалов, размещение вторых маркерных перепадов и интервалов в сигналах записи блоков на позициях, соответствующих минимальным значениям разностей суммарных длительностей интервалов противоположных уровней сигналов записи блоков, дополнение длительности одного из маркерных интервалов блоков до равенства нулю указанных разностей и запись сформированных последовательностей маркерных и информационных интервалов и перепадов по двум уровням сигналов записи блоков ...

ИНФОРМАЦИОННЫЙ НОСИТЕЛЬ ДАННЫХ И СПОСОБ И УСТРОЙСТВО ДЛЯ ЗАПИСИ/ВОСПРОИЗВЕДЕНИЯ ДАННЫХ НА НЕГО

... 1. Информационный носитель данных, имеющий множество слоев записи, причем каждый слой содержит область данных пользователя, на которой данные записаны посредством головки записи/считывания, причем данные записаны в порядке слоев записи от самого ближнего до самого дальнего от головки записи/считывания, в котором: записываемая область в области данных пользователя первого слоя записи, на котором данные должны быть записаны, является меньшей, чем записываемая область в области данных пользователя второго слоя записи между головкой записи/считывания и первым слоем записи. 2. Информационный носитель данных по п.1, в котором первый слой записи содержит незаписанные области на внутренней и внешней окружностях области данных пользователя, причем каждая незаписанная область соответствует приблизительно половине количества дорожек, через которые луч записи может проходить на второй слой записи, чтобы записывать информацию на первый слой записи. 3. Информационный носитель данных по п.1, в котором ...

НОСИТЕЛЬ ЗАПИСИ, ИМЕЮЩИЙ СТРУКТУРУ ДАННЫХ ДЛЯ УПРАВЛЕНИЯ, ПО КРАЙНЕЙ МЕРЕ, ОБЛАСТЬЮ ДАННЫХ НОСИТЕЛЯЗАПИСИ, И СПОСОБЫ И УСТРОЙСТВА ЗАПИСИ И ВОСПРОИЗВЕДЕНИЯ

... 1. Носитель записи, имеющий структуру данных для управления областью данных носителя записи, содержащий временную зону управления дефектами, в которой хранится первый блок данных, причем первый блок данных включает в себя информацию о последовательной записи и временную структуру определения, информация о последовательной записи предоставляет информацию о зонах непрерывной записи в области данных носителя записи, а временная структура определения содержит, как минимум, один указатель информации во временной зоне управления дефектами. 2. Носитель записи по п.1, в котором первый блок данных имеет размер, как минимум, один кластер. 3. Носитель записи по п.2, в котором один сектор первого блока данных отдано временной структуре определения, и не больше чем 31 сектор первого блока данных отданы информации о последовательной записи. 4. Носитель записи по п.3, в котором первый сектор информации о последовательной записи расположен рядом с временной структурой определения. 5. Носитель записи по ...

УСТРОЙСТВО ЗАПИСИ ВОСПРОИЗВЕДЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ

Изобретение относится к устройствам с цифровой магнитной записью. Сущность: устройство содержит блок управления, источник тактовых импульсов при записи и источник тактовых импульсов при воспроизведении и каналы записи-воспроизведения, первый элемент ИЛИ, счетчик. Каждый канал содержит источник информации, первый элемент И, усилитель записи, подключенный к головке записи, головку воспроизведения, подключенную через усилитель воспроизведения к формирователю, второй элемент ИЛИ, мультиплексор, третий элемент ИЛИ, второй, третий, четвертый элемент И, декодер, кодер. Вход кодера в каждом канале подключен к источнику информации, а выход - к одному входу первого элемента И. Другой вход элемента И подключен к одному входу блока управления и одному входу второго элемента И, а выход - к одному входу второго элемента ИЛИ, другой вход элемента ИЛИ подключен к выходу третьего элемента И, подключенного одним входом к выходу формирователя, а другим входом - к другому выходу блока управления и одному входу ...

Способ интеллектуально-адаптивной аналоговой магнитной записи цифровой информации

Способ интеллектуально-адаптивной аналоговой магнитной записи цифровой информации, включающий образование из двоичных сигналов кодовых групп, формирование отрезков синусоидального сигнала со значениями экстремумов амплитуды, зависящими от установленных максимальных и минимальных значений экстремумов амплитуды отрезков и от значений соответствующих кодовых групп, и запись отрезков синусоидального сигнала на магнитный носитель, отличающийся тем, что устанавливают эталонную последовательность двоичных кодов с различными разрядностью и значениями, формируют в соответствии с кодами эталонной последовательности и записывают на носитель диагностические последовательности отрезков синусоидального сигнала, каждую из которых формируют при определенном сочетании значений длительности и максимальных и минимальных значений экстремумов амплитуды отрезков и в которых текущие значения экстремумов амплитуды отрезков зависят от значений соответствующих им двоичных кодов эталонной последовательности, до записи ...

НОСИТЕЛЬ ЗАПИСИ СО СТРУКТУРОЙ ДАННЫХ ДЛЯ УПРАВЛЕНИЯ ОСНОВНЫМИ ДАННЫМИ И ДАННЫМИ ДОПОЛНИТЕЛЬНОГО СОДЕРЖИМОГО К НИМ И СПОСОБЫ И УСТРОЙСТВА ЗАПИСИ И ВОСПРОИЗВЕДЕНИЯ

... 1. Носитель записи со структурой данных для управления данными дополнительного содержимого к основным данным, записанным на носителе записи, содержащий область данных, где хранится, по меньшей мере, один файл клипа, включающий основные данные и/или данные дополнительного содержимого к основным данным; и навигационную область, где хранится файл информации о клипе, включающий информацию для указания, содержит ли файл клипа данные дополнительного содержимого. 2. Носитель записи по п.1, в котором файл информации о клипе дополнительно включает информацию, указывающую, требуется ли сетевая авторизация для проигрывания данных дополнительного содержимого. 3. Носитель записи по п.2, в котором носитель записи хранит сетевой адрес внешнего сервера поставщика информации, с помощью которого проводится сетевая авторизация. 4. Носитель записи по п.3, в котором сетевой адрес хранится в навигационном файле дополнительного содержимого, связанном с данными дополнительного содержимого. 5. Носитель записи по ...

ПОЛИСТЕРЕО-СПОСОБ ЦИФРОВОГО КОДИРОВАНИЯ СТЕРЕОФОНИЧЕСКОГО СИГНАЛА

В известных в настоящее время способах трансляции и звукозаписи стереосигнала правый и левый каналы считаются независимыми и передаются по отдельности, в результате чего суммарная полоса частот или цифровой поток при кодировании по меньшей мере удваивается по сравнению со случаем кодирования монофонического сигнала. Предлагаемый способ заключается в раздельном кодировании монофонического сигнала, состоящего из суммы сигналов правого и левого каналов, и сигналов, содержащих сведения о формах текущих спектров правого и левого каналов. При этом монофонический сигнал преобразуется в последовательность импульсов одинаковой величины.

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Способ записи-воспроизведения многоканальной цифровой информации, основанный на формировании при записи на носитель для каждой строки информации контрольного разряда в дополнительном канале путем суммирования по модулю 2 не совпадающих между собой информационных разрядов по одному в каждом канале в двух направлениях, формировании при воспроизведении признаков ошибок при отклонении от четности суммы информационных и контрольного разрядов, соответствующих суммируемым разрядам и формируемому контрольному разряду при записи, сравнении между собой признаков ошибок, определении дефектного канала по длительности интервала между совпавшими признаками одного и того же дефекта, инвертировании дефектных разрядов, соответствующих признакам ошибок, отличающийся тем, что коммутируют при записи информационные и дополнительный каналы на все дорожки носителя поочередно, осуществляют при воспроизведении обратную коммутацию информации дорожек на информационные и дополнительный каналы, сравнивают признаки ...

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Способ адаптивной аналоговой записи потоков цифровой информации с защитой от дефектов носителя, включающий образование из информационных, контрольных и служебных кодовых групп последовательности блоков, разбиение последовательности блоков на подпоследовательности и дополнение каждой подпоследовательности служебными кодовыми группами и одним или несколькими дефектозащитными блоками контрольных кодовых групп, формирование сигналов записи подпоследовательностей блоков в виде последовательностей отрезков синусоидального сигнала со значениями экстремумов амплитуды, соответствующими заданным максимальным и минимальным их значениям и значениям соответствующих кодовых групп подпоследовательностей, запись сигналов записи подпоследовательностей блоков на носитель и их контрольное считывание непосредственно после записи с временным сохранением в скользящем режиме считанных и соответствующих им исходных подпоследовательностей, обнаружение дефектных подпоследовательностей и дефектных блоков в них и ...

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Изобретение относится к магнитной записи, а именно к устройствам для магнитной записи-воспроизведения цифровой информации. Двоичное число, подаваемое по входным шинам 2 информации, записывается в первый регистр 1 по сигналу сопровождения, поступающему по входной шине 12 сигнала управления. Одновременно сигнал сопровождения- сбрасывает триггер 26 и устанавливает триггер 25 в единичное состояние. Триггер 25 подключает цифроаналоговый преобразователь 3 к интегратору 18, который формирует перепад напряжения, крутизна которого определяется двоичным числом в первом регистре 1. Интегратор 18 через усилитель 7 записи воздействует на магнитную головку 4 записи, обеспечивающую намагничивание носителя 6 магнитной записи. Интегратор 18 обеспечивает также срабатывание компаратора 19, воздействующего на одновибратор 20, последний формирует импульс, который через элемент 21 задержки устанавливает триггер 25 в нулевое состояние. Триггер 25 обеспечивает подключение к интегратору 18 источника 35 эталонного ...

Устройство для поиска информации на магнитной ленте

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Устройство для воспроизведения цифровой информации с носителя магнитной записи

Изобретение относится к устройствам для воспроизведения цифровой информации с носителя магнитной записи . Цель изобретения - уменьшение погрешности воспроизведения цифровой информации с носителя магнитной записи . Устройство содержит магнитную головку 1, усилитель 2 воспроизведения , элемент 3 амплитудно-частотной коррекции, пороговые элементы 4 и 16, элементы ИЛИ 5,17 и 18, усилительограничитель 6, демодулятор 7, формирователь 8 сигнала пуска, триггеры 9 и 10, счетчики 11,12 и 13, блок 14 установки сдвига синхросигнала, генератор 15 импульсов. В устройство введены триггер 20, входная шина 21 синхросигнала , дешифратор 22, элементы И 23 и 24, инверторы 25 и 26. Введение новых элементов и образование новых связей между элементами устройст ва позволяет достичь цель изобретения . При отсутствии глубоких выпаданий воспроизведенного фазрмодулиро- ванного (ФМ) сигнала пороговые элементы 4 и 16 формируют прямоугольные сигналы, которые через элемент ИЛИ 5 поступают на элемент И 24. Сформированный ...

Устройство для воспроизведенияцифРОВОй иНфОРМАции C НОСиТЕляМАгНиТНОй зАпиСи

Способ магнитной записи цифровой информации

Способ магнитной записи цифровой информации

Изобретение относится к способам накопления информации, а именно к магнитной записи цифровой информации. Целью изобретения является повышение плотности записи цифровой информации за счет увеличения защищенности сигнала записи и от межсимвольных помех, Магнитную запись цифровой информации осуществляют частотно-фазовой манипуляцией двоичного фазоманипулированного сигнала сигналом несущей частоты с непрерывной фазой и с непрерывной производной фазы сигнала по времени. Соседним символам двоичного фазоманипулированного сигнала ставят в соответствие полупериоды сигнала несущей частоты противоположной фазы, причем фазу сигнала несущей частоты изменяют на противоположную на каждой границе между соседними символами двоичного фазоманипулированного сигнала. В течение каждого символа формирование нулевой постоянной составляющей сигнала несущей частоты осуществляют тем, что середине длительности символа двоичного фазоманипулированного сигнала ставят в соответствие нулевое значение сигнала несущей частоты ...

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Изобретение относится к области магн.записи. Цель изобретения - снижение погрешности детектирования за счет исправления информации при одноразрядных вьтадениях сигнала. На входах элемента И 7присутствуют сигналы с выходов триггера 6, триггера 8 и импульсы третьей последовательности . При совпадении этих сигналов на выходе элемента И 7 формируются импульсы, устанавливающие в единичное состояние счетный триггер 10, который формирует синхроимпульсы, поступающие на шину 16 и на один из входов элемента И 14, иа второй вход которого поступают импульсы третьей последовательности. При совпадении этих сигналов на выходе элемента И 14 формируются импульсы информационных 1. На входах элемента И 21 присутствуют импульсы с выхода триггера 24, импульсы информационных 1 и проинвертированные элементом НЕ 23 импульсы выпадения. При их совпадении на выходе элемента И 21 формируются импульсы, соответствующие единичным выпадениям импульсов 1, которые суммируются на элементе ИЛИ 20 с задержанными элементом ...

Способ магнитной записи цифровой информации и устройство для его осуществления

Изобретение относится к приборостроению , а именно к технике магнитной записи, и может использоваться в аппаратуре регистрации и внешних запоминающих устройствах вычислительной техники. Цель изобретения - повышение верности результата записи-воспроизведения и помехоустойчивости за счет снижения межсимвольных искажений воспроизводимых сигналов и увеличения ...

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Изобретение относится к магнитной записи и позволяет снизить погрешности устройства. В режиме записи цифровой информации импульсные последовательности заданных частот в соответствии с параллельным кодом с выходов регистра памяти через коммутатор 15 поступают на входы полосовых фильтров 17, формирующих синусоидальные сигналы, и через ключевые элементы 18, сумматор 19, усилитель 3 записи - на магнитную головку 4. Синусоидальный сигнал, воспроизводимый магнитной головкой 6 и усилителем 7 воспроизведения , поступает на вход компаратора 11, где формируется последовательность импульсов, в которой на месте дефектов магнитного носителя импульсы отсутствуют. Счетчик 12 импульсов отсчитывает определенное число поступаюш.их импульсов за интервал времени, равный периоду минимальной частоты следования одного из мультивибраторов 14. 2 с.п.ф-лы, 2 ил. (Л to ю ОО СП ю ...

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Изобретение относится к магнитной записи и позволяет повысить достоверность воспроизведения цифровой информации. В процессе воспроизведения триггер 5 устанавливается в состояние, обеспечивающее перевод блока 7 магнитной записи-воспроизведения (МЗВ) в режим воспроизведения. Блок 7 формирует импульсный сигнал, передние фронты которого соответствуют изменениям намагниченности носителя магнитной записи. Импульсный сигнал с блока 7 МЗВ поступает на триггер 15 и на управляемый генератор 10, восстанавливающий частоту синхронизации. При этом по сигналу с второй управляющей щины 20 элемент И 1 1 и триггер 6 обеспечивают установление правильной тактовой синхронизации . На триггер 6 воздействует триггер 15, который воздействует также на триггер 17 и на регистр 8. Сигнал. соответствуюии1Й импульсному сигналу с блока 7 .МЗВ. подается с триггера 17 на регистр 8, воздействующий на блок 9 памяти. Информация с блока У2 9 памяти поступает на выходную информационную щину 14. При этом блок 9 памяти (Л воздействует ...

Устройство для цифровой магнитной записи и воспроизведения

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УСТРОЙСТВО ДЛЯ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ

Устройство для декодирования адаптивного канального кода

Устройство для декодирования канального кода относится к области техники цифровой записи информации на движущемся носителе и решает задачу повышения достоверности декодирования адаптивного канального кода при воспроизведении с движущегося носителя за счет компенсации влияния случайных отклонений скорости движения носителя. Преобразователь 5 период - код, соединенньй с входом 11 устройства через формирователь 10 импульсов, дополнительный преобразователь 4 кода, накапливающий сум- матор 7 и преобразователь 6 код - частота, образуют контур компенсации отклонения скорости движения носителя . Преобразователь 3 кода преобразует результаты измерения длительностей интервалов данного канального кода в двоичньм код, а неравномерность поступления кода компенсируется путем использования блока 1 памяти и формирователя 2 временной последовательности Синхронизация в устройстве осущетвляется от одного синхронизирующего генератора 12. 1 ил. СЛ .С ...

Устройство для синхронизации воспроизведения цифровой магнитной записи

Изобретение относится к магнитной записи, а именно к устройствам для .синхронизации воспроизведения цифровой магнитной записи. Целью изобретения является повышение достоверности 1воспроизвбдения информации за счет улучшения параметров системы ФАПЧ устройства. Цель достигается путем помехоустойчивого декодирования промежутков синхронизации и использования режима частотной автоподстройки для ускорения отработки реальной частоты и фазы входных сигналов воспроизведения. Устройство содержит первьй мультиплексор 1, ЛС- триггер 7, два D-триггера 9,10, ключи 12,13 заряда и разряда, ФНЧ 14, генератор управляемый напряжением 15, делитель 16 частоты, Т-трйггер 17, элемент 4 задержки, элемент 2И-НЕ I1, а также введенные в него второй мультиплексор 18, регистр сдвига 2, первый 5 и второй 8 инверторы, элемент 2И 3 и детектор 6 нулей, которые соединены между собой и с указанными функциональными элементами соответствующими связями. I э.п. ф-лы, 3 ил. i (f) ...

СПОСОБ МАГНИТНОЙ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ

Способ однодорожечной старт-стопной магнитной записи-воспроизведения

Изобретение относится к магнитной записи и позволяет повысить достоверность результата воспроизведения. Счетчик 13 производит измерение интервала времени между моментами воспроизведения стартового импульса и дополнительного стартового импульса , по последнему импульсу дод счетчика 13 передается в регистр 17 сдвига и сдвигается на один шаг. После этого счетчик 13 обнуляется и вновь заполняется импульсами с входной шины 14 опорного сигнала. В момент равенства кодов регистра 17 сдвига и счетчика 13 цифровой компаратор 18 выдает импульс, который подсчитывается счетI чиком 15. При этом первый импульс с цифрового компаратора 18 совпадает со старто (Л вым импульсом. Содержимое счетчика 15 равно значению кодового слова. 2 ил.

Устройство для многоканальной магнитной записи цифровой информации

Устройство для двухканального воспроизведения блочной цифровой информации

Изобретение относится к приборостроению . Цель изобретения - повышеItf кие верности воспроизведения. При выпадении сигнала воспроизведения триггер 15 фиксирует наличие сигнала паузы, триггер 22 остается в состоянии воспроизведения информации, так как не срабатывает блок 21 пересчета. Дешифратор 12 продолжает выдавать импульс с тактовой частотой, задержанной на половину такта. Первый из них опрокидывает триггер 15, и устройство продолжает вырабатывать кодовые и тактовые импульсы по состоянию триггеров 5 до появления воспроизведенного сигнала с выходов формирователей 3 импульсов. 1 ил. (Л со Oi ел оо ...

УСТРОЙСТВО ДЛЯ ВОСПРОИЗВЕДЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ С НОСИТЕЛЯ МАГНИТНОЙ ЗАПИСИ

Способ магнитной записи цифрового кода

Аппарат магнитной записи

Устройство для выделения цифровой информации из воспроизводимого сигнала

УСТРОЙСТВО ДЛЯ ВЫДЕЛЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ ИЗ ВОСПРОИЗВОДИМОГО СИГНАЛА, содержащее усилитель воспроизведения, подсоединенный входом к магнитной головке, а выходом - к входу амплитудного корректора , выход которого через первый корректор формы сигнала и первый симметричный ограничитель соединен с первым входом блока сравнения на эквивалентность, а через дифференциатор и второй корректор формы сигнала - с входом второго симметричного ограничителя, подключенного выходом к второму входу блока сравнения на эквивалентность и соединенного через формирователь импульсов с входом генератора синхроимпульсов , подсоединенного выходом к выходной шине синхросигнала, и первый и второй элементы И, подключенные выходами к входам элемента ИЛИ, соединенного выходом с выходной шиной цифровой инфор .мации, отличающееся тем, что, с целью повышения помехоустойчивости, в него введены первый и второй формирователи импульсов с задержкой на половину тактового периода, подсоединенные входами соответственно к первому ...

Способ записи цифровой информации

Устройство для магнитной записи иВОСпРОизВЕдЕНия цифРОВОй иНфОРМАции

УСТРОЙСТВО ВОСПРОИЗВЕДЕНИЯ СИГНАЛОВ ЦИФРОВОЙ ИНФОРМАЦИИ С НОСИТЕЛЯ МАГНИТНОЙ ЗАПИСИ

Устройство для записи цифровой информации

К УСТРОЙСТВО ДЛЯ ЗАПИСИ ЦИФРОВОЙ ИНФОРМАЦИИ, содержащее последовательно соединенные магнитную головку , усилитель записи и счетный триггер, формирователь импульсов, первый и второй регистры сдвига, информационную шину и первую синхронизирующую щину, подключенные к информационному и синхронизирующим входам первого регистра сдвига, вторую синхронизирующую шину, подсоединенную к первому входу формирователя импульсов , отличающееся тем, что, с целью снижения погрешности записи цифровой инCit формации путем ее групповой синхронизации , в него введены счетчик импульсов, статический регистр, коммутатор и формирователь сигнала обратной связи, причем вход счетчика импульсов и второй вход формирователя импульсов соединены с первой синхронизирующей шиной, формирователь импульсов подключен выходом к синхронизирующему входу второго регистра сдвига, подсоединенного первым и вторым входами записи соответственно к выходу счетчика импульсов и входу считывания первого регистра сдвига, который соединен выходом ...

Устройство для воспроизведения цифровой информации с носителя магнитной записи

УСТРОЙСТВО ДЛЯ- ВОСПРОИЗВЕДЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ С НОСИТЕЛЯ МАГНИТНОЙ ЗАПИСИ, содержащее входную шину, соединенную через формирова-t тель импульсов с первым входом первого элемента И, .подключенного выходом к выходной шине кода, и с первым входом второго элемента И, источник сигнала опорной частоты, подсоединенный выходом к входу первого делителя частотыи к входу второго делителя частоты, соединенного выходом с первым входом третьего элемента И, второй вход которого подключен к инверсному выходу триггера , элемент ИЛИ , подсоединенный первым входом к выходу четвертого элемента И, первый счетчик, соединенный выходами с входами пятого элемента И, второй счетчик и выходную шину синхроимпульсов, о т л ич а. ющ е е с я тек, что, с целью уменьшения погрешности воспроизведения цифровой информации, в него введены дополнительный триггер, подсоединенный первым входом к выходу второго элемента И, соединенного вторым входом с прямым выходом триггера, инверсный выход которого подключен к второму ...

Устройство для магнитной записи

УСТРОЙСТВО ДЛЯ МАГНИТНОЙ ЗАПИСИ, содержащее блок буферной памяти, вход которого соединен с шиной данных, а выход - с магнитным накопителем , два адресных счетчика, соединенных через мультиплексор с адресными входами блока буферной памяти, коммутатор. два выхода которого подключены к в адресных счетчиков, реверсивный сч( управляющие входы которого и упра щие входы магнитного накопителя сое ны с выходами предпоследних раз адресных счетчиков, первый элемен первый вход которого соединен с первы ходом реверсивного счетчика, второй щиной синхросигналов, а выход - с пс входом коммутатора, отличающееся что, с целью повышения помехозащ ности, в него введены дополнительны1 мент И и элемент ИЛИ, входы кот соединены с первым и вторым выходал версивного счетчика, а выход подключе ному из входов дополнитльного элемен другой вход последнего подключен к в управления магнитного накопителя, а соединен с вторым входом коммут; ...

Устройство для воспроизведения цифровой информации

Изобретение относится к магнитной записи и позволяет повысить верность воспроизведения информации, для этого информация заносится в буферное запоминающее устройство 2, считывание из которой производится стабильной частотой от кварцевого генератора 7 через делитель 9 частоты . Потеря информации исключается путем управления скоростью движения магнитного носителя в зависимости от заполнения памяти. Дпя уменьшения влияния выпадений, вызывающих сбои тактовой частоты и нарушение очередности адресов в буферном запоминающем устройстве 2, управление скоростью осуществляется через реверсивный счетчик 4, работающий от кварцевого генератора 7, частота которого постоянна и не зависит от сигналов воспроизведения . Коэффициент деления управляемого делителя 6 частоты при наличии выпадений и без них будет поочередно изменяться на единицу, что гарантирует синхронную работу ведущего привода магнитного запоминающего .устройства 1, 1 ил. (Л 00 ю to о 05 ...

Способ магнитной записи-воспроизведения цифровой информации

Способ записи цифровой информации

Устройство для цифровой магнитной записи

Устройство для записи на магнитную ленту прерывистого потока дискретной информации

Способ магнитной записи двоичного кода

Устройство для магнитной записи цифровой информации

Многоканальное устройство для воспроизведения цифровой информации

Устройство для магнитной записи

Устройство для записи и считывания информации

Устройство для воспроизведения цифровой информации

Устройство для цифровой магнитной записи

Устройство для магнитной записи и воспроизведения двоичной информации

Устройство поиска адреса в системах памяти с магнитными барабанами или дисками

Устройство для воспроизведения цифровой информации

Способ магнитной записи цифровых сигналов с компенсацией ошибок размещения информационных знаков

CПOCOБ MAГHИTHOЙ ЗAПИCИ ЦИФPOBOЙ ИHФOPMAЦИИ

Устройство для магнитной записи цифровой информации

Устройство для воспроизведения цифровой информации с носителя магнитной записи

Устройство для воспроизведения цифровой информации с магнитного носителя

Устройство для воспроизведения с носителя магнитной записи

Устройство для воспроизведения цифровых сигналов с носителя магнитной записи

Изобретение относится к магнитной записи. Цель изобретения - уменьшение погрешности воспроизведения цифровых сигналов. Формирователь 34 импульсов вырабатывает синхроимпульсы по перепадам от низкого уровня к высокому (/) г$- 26 ...

Устройство для магнитной записи аналаговой и цифровой информации

Устройство для цифровой магнитной записи

Устройство для воспроизведения цифровой информации

Устройство для восстановления импульсов синхронизации при воспроизведении цифровой информации

Устройство для магнитной записи двоичной информации

Изобретение относится к приборостроению , а именно к технике магнитной записи. Цель изобретения - повышение плотности записи. Цель достигается тем, что в устройство для магнитной записи цифровой информации , содержащее генератор 1 импульсов, счетчик 2, мультиплексор 3 (блок кодирования) и формирователь 4 биполярных импульсов, введен триггер 6 (трехразрядный ), включенный перед входом блока 3 кодирования. 3 табл., 3 ил.

Устройство для воспроизведения цифровой информации с магнитного носителя

Изобретение относится к средствам магнитной записи. Цель изобретения - повышение верности воспроизведения данных. Устройство содержит детектор 1, интегрирующий усилитель 2, генератор 3, триггер 4, элемент J7. ;2 5 задержки, усилитель 6,преобразователь 7 напряжение-интервал, элемент ИЛИ 8, шину 9 формирования импульсов окна, шину 10 задержанных данных шины 11 воспроизведенных: импульсов. Введение новых элементов и образование новых связей между элементами устройства позволяет повысить динамическую точность синхронизации.При отклонении частоты воспроизведенных импульсов от номинальной образуется сдвиг фазы импульсов на выходе генератора 3 относительно воспроизведенных импульсов.Величина сдвига перед- него фронта импульсов генератора 3 компенсируется величиной приращения длительности импульса, формируемого на выходе преобразователя 7 напряжение-интервал , 1 з.п, ф-лы, 3 ил. (Л У 3 -3 J 00 со ts3 со О5 00 ж ю ...

Устройство для воспроизведения с носителя магнитной записи

Устройство для формирования сигналов кодирования участков магнитной ленты

Изобретение может быть использовано при записи цифровой информации на магнитную ленту в аналоговых аппаратах магнитной записи. Цель изобретения - увеличение плотности записи информации. Импульсы тактовой частоты от генератора 1 поступают на вход распределителя 2, с коК . I Е (гторого подаются на смеситель 4 через ключи 3, а с выхода смесителя 4 поступают на вход блока 5 преобразования кода с возвращением к нулю в двухфазный код. В формирователе 6 осуществляется формирование фронтов импульсной последовательности двухфазного кода. При воспроизведении получается сигнал, в котором возможно амплитудное выделение синхроимпульсов кодовых слов, а также формирование импульсов , определяющих исходный код. Применение блока 5 преобразования кода, формирователя 6 и образование новых связей позволяет исключить постоянный опрсдс.чн- тель начала кодового слова из информапион ной последовательности и совместить его с концом слова. 1 ил. ( (Л с I i о 4 ...

Устройство для восстановления тактовых импульсов

УСТЮЙСТВО ДЛЯ ВОССТАНОВЛЕНИЯ ТАКТОВЫХ ИМПУЛЬСОВ, содержащее формирователь тактовых импульсов, первый триггер, счетчик, генератор импульсов, о тли чающееся тем, что, с целью повышения точности и помехоустойчивости устройства, в него введены формирователь признака начала информации, форкшрователь признака конца информации, первый и второй элементы И, первьй, второй и третий элементы ИЛИ, дешн4фатор и второй триггер, при этом формирователь тактовых импульсов подключен к первому входу первого элемента И, выход последнего и выход формирователя признака начала информации через первый элемент ИЛИ подключены к установочному входу счетчика и к первому входу второго элемента ИЛИ, выход которого подключен к единичшлм входам первого и второго триггеров, выход формирователя признака конца информации подключен к нулевому входу первого триггера, прямой выход этого же триггера и выход генератора импульсов подключены-к входам второго элемента И, выход которого подключен к счетному входу счетчика, а выходы ...

Устройство для двухканального воспроизведения блочной цифровой информации

УСТРОЙСТВО ДЛЯДВУХКАНАЛЬ-НОГО ВОСПРОИЗВЕДЕНИЯ БЛОЧНОЙ ЦИФРОВОЙ ИНФОРМАЦИИ по авт.СВ. № 924746, отличающееся тем, что, с целью уменьшения при выпадениях вероятности смещения на магнитном носителе отпечатков сигналов, в него введены дополнительный формирователь им- i 113 пульсов, шестой элемент ИЛИ и последовательно соединенные блок пересчета седьмой элемент И, пятый триггер, восьмой элемент И и седьмой элемент ИЛИ, при этом второй вход седьмого элемента И связан с входом элемента НЕ, вход блока пересчета -. с шиной синхрониэации, выход этого же блока через дополнительный формирователь с вторым входом пятого триггера, второй вход восьмого элемента И - с выходом шестого элемента ИЛИ, входы которого соединены с счетн.ыми входами счетных триггеров, второй вход седьмого элемента ИЛИ с выходом второго элемента И, а выход седьмоi го элемента ИЛИ - с шиной синхронизации . W ...

Способ записи цифровой информации на магнитный носитель

Изобретение предназначено для записи цифровой информации на магнитный носитель. Цель изобретения - повышение плотности записи информации при сохранении параметра самосинхронизации и окна детектирования. Способ записи цифровой информации осуществляют путем ввода трехинтервальный БВНМ-сигнал нечетного числа дополнительных перепадов тока записи с частотой, превышающей верхнюю граничную частоту канала записи-воспроизведения, причем дополнительные перепады тока записи вводят в каждом периоде БВНМ-сигнала - в одном из двух его частей, или в интервал с высоким уровнем, или в интервал с низким уровнем, независимо от поступающей информации. Устройство, работающее по способу, содержит блок синхронизации 1, блок кодирования 2, блок ввода дополнительных перепадов 3, блок записи 4. 2 ил.

Устройство для магнитной записи и воспроизведения цифровой информации

УСТРОЙСТВО ДЛЯ МАГНИТНОЙ ЗАПИСИ И ВОСПРОИЗВЕДЕНИЯ ЦИФРОВОЙ ИНФОРМАЦИИ, содержащее блок декодирования , выходы которого соединены с входами выходного буферного регистра , подключенного выходом ft информационному входу блока обработки ийформации , соединенного информационным выходом с первым входом входного буферного регистра,подсоединенного вторым входом к управляющему выходу блока обработки информации, подключенному к первому входу формирователя синхроимпульсов соединенного вторым входом с выходом первого из генераторов , а первым выходом - с управляющим входом блока обработки информации , формирователь сигнала записи, подключенный выходом к входу узла записи-воспроизведения, выход которого соединен через усилитель воспроизведения с интегратором-дифференциатором ,элементы И,элеме1 р ИЛИ,ограничители ,компараторы и элемент задержки ,о т л и ч а ю щ ее с я тем, что, с целью повышения плотности записи и уменьшения погрешности воспроизведения , в него введены включенные последовательно элемент ...

Устройство записи и воспроизведения цифровой информации на магнитном носителе

Изобретение относится к области приборостроения , а именно к цифровым запоминающим устройствам на движущемся носителе. Изобретение позволяет повысить 1 Изобретение относится к приборостроению , а именно к цифровым запоминающим устройствам на движущемся носителе. Целью изобретения является повыщение помехоустойчивости при наличии выпадений. На чертеже приведена структурная схема предлагаемого устройства. Синхронное запоминающее устройство содержит илину 1 данных, щину 2 синхросигнала , делитель 3 частоты, буферный блок 4, формирователь 5 маркеров, блок 6 уплотнения , блок 7 выделения маркеров, кодер 8, декодер 9, блок 10 головок записи, блок 11 головок воспроизведения, резонансный усилитель 12, формирователь 13 пилот-сигнала, головку 14 записи пилот-сигнала, головку 15 воспроизведения пилот-сигнала, лентопротяжный механизм 16, электродвигатель 17, датчик 18 оборотов, коммутатор 19 режимов работы, щину 20 команд и блок 21 регулирования . Шина 1 данных подключена к первому входу буферного ...

Способ магнитной записи цифровой информации

Изобретение относится к приборостроению, а именно к технике магнитной записи, и может быть использовано в устройствах регистрации информации и внешних запоминающих устройствах вычислительной техники. Цель изобретения - повышение плотности записи. Запись на носитель магнитной записи осуществляют короткими прямоугольными импульсами чередующейся полярности, тактовый интервал Т сигнала записи выбирают из условия Т = (1,5...2) δ/*98H, где δ - рабочий зазор магнитной головки, ν - скорость движения носителя магнитной записи. Сигналы исходной информационной последовательности разделяют на трехбитовые группы, и каждую группу записывают с тактовым периодом 4Т. Для информационных "0" формируют одиночные импульсы с интервалом между ними 1Т. Для информационных "1" формируют пачку из трех импульсов с интервалами 1Т между пачками и одиночными импульсами "0". Интервалы между импульсами в пачке устанавливают @ 0,5Т, если в трехбитовой группе только одна "1", и 0,25Т, если в трехбитовой группе две "1". Трехбитовую ...

Устройство для многоканальной магнитной записи сигналов цифровой информации

УСТРОЙСТВО ДЛЯ МНОГОКАНАЛЬНОЙ МАГНИТНОЙ ЗАПИСИ СИГНАЛОВ ИНФОРМАЦИИ, содержащее информационные каналы, состояние из источника информации, последовательно соединенньк первого элемента ИЛИ, счетного триггера и усилителя записи, подключенного выходом к одному входу блока магнитных головок, а также первого элемента И, и опорный канал, состоящий аз последовательно соединенных источника синхрониэирукждах импульсов, первого ждущего мультивибратора , первого формирователя импульсов , а также содержащий первый элемент И, счбтчик, второй ждущий мультивибратор , второй элемент И и первый элемент НЕ, отличающеес я тем, что, с целью уменьшения погрешности формирования антиперекосных маркеров при воздействии ряда дестабилизирующих факторов, в него введены в информационные каналы последовательно соединенные второй элемент ИЛИ и триггер, а также последовательно соединенные второй элемент и, третий элемент ИЛИ и элемент НЕ, в опорный канал - второйи треJrий элв1у1енты НЕ, последовательно соединенные третий ...

Способ коррекции временных искажений в воспроизведенном сигнале

... 1. СПОСОБ КОРРЕКЦИИ ВРЕМЕННБ1Х ИСКАЖЕНИЙ В ВОСПРОИЗВЕДЕННОМ СИГНАЛЕ, заключающийся в формировании сигнала -воспроизведения, пропорционального изменению намагниченности носителя, формировании импульсного сигнала по экстремумам сигнала воспроизведения и формировании выходного сигнала; принимающего «единичные значения уровня в интервалах тактов основного синхросигнала, в течение которых появляются импульсы импульсного сигнала, отличающийся тем, что, с целью повышения верности воспроизведения, из сигнала воспроизведения формируют выпрямленный сигнал, формируют знаковый сигнал с двумя уровнями, соответствующими знакам разности абсолютных значений крутизны переднего и заднего фронтов импульсов выпрямленного , сигнала, формируют дополнительный синхросигнал с меньшей двух скважностью импульсов, середины интервалов между импульсами которого совпадают с серединами тактов основного синхросигнала , выделяют импульсы импульсного сигнала, совпадающие по времени с импульсами дополнительного синхросигнала ...

Способ записи-воспроизведения сигналов синхронизации в цифровом канале магнитной записи

СПОСОБ ЗАПИСИ-ВОСПРОИЗВЕДЕНИЯ СИГНАЛОВ СИНХРОНИЗАЦИИ В ЦИФРОВОМ КАНАЛЕ МАГНИТНОЙ ЗДПИСИ, заключающийся в записи совместно с сигналами «единиц служебных сигналов «нулей, при этом определяют количество следующих друг за другом сигналов «нулей и при превыщении им выбранного для используемого канала числа и записывают на магнитный носитель служебный сигнал в каждой серии из П сигналов «нулей, отличающийся тем, что, с целью повыщения верности записи и воспроизведения служебных сигналов синхронизации , запись сигналов каждой серии «нулей производят основным перепадом тока перемагничивания носителя на границе (в середине ) одного из символьных интервалов внутри серии, окруженным с обеих сторон вспомогательными перепадами тока одинакового направления, а при воспроизведении выделяют сигналы, соответствующие вторым экстремальным точкам воспроизводимых служебных однополярных импуль сов, и используют их в качестве сигналов (Л синхронизации.

Способ магнитной записи цифровой информации

Изобретение относится к технике цифровой магнитной записи и может использоваться в разнообразных накопителях цифровых данных с повышенной плотностью записи. Цель изобретения - повышение плотности записи. Способ основан на записи кодовых групп из шестнадцати информационных и двух контрольных разрядов одним сигналом записи - трипульсом. Способ обеспечивает повышение плотности записи до 3,26 бит на минимальный интервал при сохранении возможности исправления групповых сбоев (выпадений) заданной максимальной длительности. 2 ил., 2 табл.

Устройство для магнитной записи и воспроизведения информации

Устройство воспроизведения сигналов цифровой информации с магнитного носителя

УСТРОЙСТВО ВОСПРОИЗВЕДЕНИЯ СИГНАЛОВ ЦИФРОВОЙ ИНФОРМАЦИИ С МАГНИТНОГО НОСИТЕЛЯ, содержащее усилитель-формирователь , первую группу из двух D -триггеров, шину выходной информации и шину импульсов синхронизации , инерционный генератор, подключенный к синхронизирующему входу первого D -триггера первой группы, информационный вход которого соединен с выходом второго D -триггера первой группы, а выход первого D-триггера соединен с шиной выходной информации, отличающееся тем, что, с целью повышения верности воспроизведения , в него введены элемент задержки , блок управляемой задержки, распределитель импульсов, блок памяти кодов задержки, вторая группаD-триггеров и элемент ИЛИ, при этом выход усилителя-формирователя соединен с входом инерционного генератора и синхронизирующими входами D -триггеров второй группы, выход инерционного генератора соединен с шиной импульсов синхронизации и через элемент задержки - с входом блока управляемой задержки, выход этого блока соединен с входом распределителя ...

Способ записи и воспроизведения служебных сигналов синхронизации на магнитный носитель

СПОСОБ ЗАПИСИ И ВОСПРОИЗВЕДЕНИЯ СЛУЖЕБНЕЛХ СИГНАЛОВ СИНХРОНИЗАЦИИ НА МАГНИТНЫЙ НОСИТЕЛЬ, основанный на записи сигналов единиц двоичного кода совместно со служебными сигналами последовательности нулей, при котором определяют число следующих подряд сигналов нулей и при превышении им заданного значения записьтают на магнитный носитель служебный сигнал в символьном интервале после регистрации данной серии следующих подряд сигналов нулей,- отличающийся тем, что, с .целью повьлшения плотности записи, служебный сигнал записывают четным и большим двух числом перепадов намагниченности в пределах символьного интервала, а при воспроизведении служебные сигналы вьаделяют путем определения временных интервалов между концом и началом сформированных при двухпороговом ограни (Л чении соседних разнополярных импуль сов воспроизведения служебного сигнала . 1 ...

Устройство для цифровой магнитной записи

Изобретение относится к технике магнитной записи на подвижный магнитный носитель и позволяет повысить точность записи за счет увеличения количества предыскажений до четырех, а также за счет того,- что для одинаковой комбинации трех соседних интервалов формируются одинаковые по величине предыскажения. Это достигается тем, что устройство дополнительно содержит четырехразрядный регистр сдвига 16, три формирователя 17-19, три элемента задержки 20-22, три двоичных счетчика 23-25, четыре элемента И 26-29, два элемента 2-2И-2ИЛИ-НЕ 30, 31, элемент 2-2-2И-ЗИЛИ-НЕ 32, два элемента И-НЕ 33 и 34 и блок 35 задержек . 4 ил.,1 табл.

Disk drive with variable incremented counting of writes to the data tracks for minimizing the effect of far track erasure

A hard disk drive (HDD) minimizes the effects of far track erasure (FTE) by counting the number of writes to the data tracks and incrementing counters based on the known effect of FTE on each track. The extent of the FTE effect is determined for each track within a range of tracks of the track being written, and based on the relative FTE effect for all the tracks in the range a count increment (CI) is determined for each track within the range. A counter is maintained for each track. For every writing to a track, a count for each track within a range of the track being written is increased by the CI value associated with the track number within the range. When the count value for a track reaches a predetermined threshold the data is read from that track and rewritten, preferably to the same track.

Gain control with multiple integrators

A method according to one embodiment includes receiving an increment signal at a first integrator when a second integrator overflows; receiving a decrement signal at the first integrator when the second integrator underflows; and incrementing or decrementing a gain applied to an analog signal based on receipt of the increment or decrement signal. A system according to one embodiment includes a first integrator configured to cause incrementing of a gain applied to an analog signal based on receipt of an increment signal when a second integrator overflows, the first integrator being configured to cause decrementing of the gain applied to the analog signal based on receipt of a decrement signal when the second integrator underflows; and the second integrator.

Signal reception apparatus and signal reception method

One embodiment provides a signal reception apparatus including: a reception module configured to receive a signal; a storing module configured to store information regarding a characteristic of the received signal; a determination module configured to read out the stored information and to determine a parameter value corresponding to the read-out information; a discrimination module configured to discriminate a noise contained in the signal, based on the signal and the determined parameter value; and an identification module configured to identify the noise contained in the signal, based on a discrimination result by the discrimination module.

Efficient connection management in a sas target

A method includes pre-configuring a hardware-implemented front-end of a storage device with multiple contexts of respective connections conducted between one or more hosts and the storage device. Storage commands, which are received in the storage device and are associated with the connections having the pre-configured contexts, are executed in a memory of the storage device using the hardware-implemented front-end. Upon identifying a storage command associated with a context that is not pre-configured in the hardware-implemented front-end, software of the storage device is triggered to configure the context in the hardware-implemented front-end, and the storage command is then executed using the hardware-implemented front-end in accordance with the context configured by the software.

Channel circuit and seek method

A channel circuit includes a reader, a decoder, a prediction module, and a seek module. The reader reads data written in a medium. The decoder performs iterative decoding of the read data. The prediction module predicts whether an early read is possible or not without waiting for arrival of the read data. The seek module continuously initiates a seek when the prediction module predicts that the read is possible.

Implementing magnetic defect classification using phase modulation

A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects.

Methods and Apparatus for Map Detection with Reduced Complexity

Methods and apparatus are provided for high-speed, low-power, high-performance channel detection. A soft-output detector is provided for processing a received signal, comprising: a forward detector for calculating forward state metrics; a backward detector for calculating backward state metrics; and a current branch detector for calculating a current branch metric, wherein at least two of the forward detector, the backward detector and the current branch detector employ trellis structures with a different number of states. A method is provided for processing a received signal using a soft-output detector, comprising: calculating forward state metrics using a forward detector; calculating backward state metrics using a backward detector; and calculating a current branch metric using a current branch detector, wherein at least two of the forward detector, the backward detector and the current branch detector employ trellis structures with a different number of states. 1. A soft-output detector for processing a received signal , comprising:a forward detector for calculating forward state metrics;a backward detector for calculating backward state metrics; andcurrent branch detector for calculating a current branch metric, wherein at least two of said forward detector, said backward detector and said current branch detector employ trellis structures with a different number of states.2. The soft-output detector of claim 1 , wherein said forward detector uses a four state claim 1 , radix 2trellis with or without feedback claim 1 , with N≧2 claim 1 , where N is a number of received samples.3. The soft-output detector of claim 1 , wherein said backward state metrics are unraveled by setting initial backward state metrics to 0 and calculating a best path leaving each current backward state in a forward direction.4. The soft-output detector of claim 1 , wherein forward branch metrics are used by said forward detector to calculate said forward state metrics and also used by ...

MAGNETIC DISK CONTROL DEVICE, MAGNETIC DISK APPARATUS, MAGNETIC DISK CONTROL METHOD AND COMPUTER PROGRAM

A magnetic disk control device according to an exemplary of the invention includes a write controller to control, in a magnetic disk having tracks, the track being a storage area made by concentrically dividing a magnetic recording layer formed onto a disk into a plurality of areas, the track being divided into a plurality of areas in a rotative direction as sectors, writing information into the each sector; and a substitution controller to make, by detecting the sector or the track written at a frequency higher than a writing frequency based on a number of times of writing by the write controller to the sector or the track and by moving information recorded in an adjacent track adjacent to a high-writing-frequency track including the detected high writing frequency sector or to a high-writing-frequency track which is detected as a high writing frequency track to a track of a substitution area. 1. A magnetic disk control device , comprising:a write controller to control, in a magnetic disk having tracks, the each track being a storage area made by concentrically dividing a magnetic recording layer formed onto a disk into a plurality of areas, the each track being further divided into a plurality of areas in a rotative direction as sectors, writing information into the each sector; anda substitution controller to make, by detecting the sector or the track written at a frequency higher than a prescribed writing frequency based on a number of times of writing by the write controller to the sector or the track per prescribed unit time and by moving information recorded in an adjacent track adjacent to a high-writing-frequency track including the detected high writing frequency sector or to a high-writing-frequency track which is detected as a high writing frequency track to a track of a substitution area set in advance, the adjacent track be in an idle status, the idle status being a status of not being used.2. The magnetic disk control device according to claim 1 , ...

DISK-DRIVE PULSE DURATION CONTROL SYSTEM

One embodiment includes a pulse duration control system for a magnetic disk-drive system. A rise delay system generates first control voltages in response to a write data input signal changing between a first state and a second state. A fall delay system generates second control voltages in response to the write data input signal changing between the first and second states. A comparator system generates a rising-edge overshoot signal and a falling-edge overshoot signal based on a comparison of the first and second control voltages. The rising-edge overshoot signal can set a duration of a positive overshoot current pulse for a write current at a transition of the write data input signal from the first state to the second state, and the falling-edge overshoot signal can set a duration of a negative overshoot current pulse for the write current at a transition from the second state to the first state. 1. A pulse duration control system for a magnetic disk-drive system , the system comprising:a rise delay system configured to generate a first plurality of control voltages in response to a write data input signal changing between a first state and a second state;a fall delay system configured to generate a second plurality of control voltages in response to the write data input signal changing between the first state and the second state; anda comparator system configured to generate a rising-edge overshoot signal and a falling-edge overshoot signal based on a comparison of the first and second pluralities of control voltages, the rising-edge overshoot signal being associated with a duration of a positive overshoot current pulse for a write current at a transition of the write data input signal from the first state to the second state, and the falling-edge overshoot signal being associated with a duration of a negative overshoot current pulse for the write current at a transition of the write data input signal from the second state to the first state.2. The system of ...

Shingled magnetic recording disk drive with compensation for the effect of far track erasure (fte) on adjacent data bands

A shingled magnetic recording (SMR) disk drive has concentric shingled data tracks having data sectors with physical block addresses (PBAs), with the tracks being arranged in annular bands separated by annular inter-band gaps. The disk drive also has an on-disk extended cache region and may have writable inter-band cache (IBC) tracks in the inter-band gaps. A count is maintained in memory for each band and each IBC, and the count is incremented for each writing to a band or an IBC. When a count for a band or IBC reaches a predetermined threshold, the data is read from the tracks in the boundary region of the adjacent band that are within the range of the FTE and that data is then written to the extended cache. The FTE-affected tracks are then invalidated, meaning that PBAs can no longer be assigned to the data sectors in those tracks.

Method and Apparatus for Reading a Non-Volatile Memory Using a Spin Torque Oscillator

A method and apparatus for reading electronic memory comprising a current source, a spin transfer oscillator, an external field source, coupled to the current source, for generating an RF signal, the spin torque oscillator positioned proximate a magnetic media comprising a plurality of bit regions of varying magnetic permeability, wherein a frequency of the RF signal varies in response to the permeability of a bit region in the plurality of bit regions being proximate the spin torque oscillator. 1. An apparatus for reading electronic memory comprising:a current source;an external magnetic field source;a spin transfer oscillator, coupled to the current source, for generating an RF signal;the spin torque oscillator positioned proximate a magnetic media comprising a plurality of bit regions of varying magnetic permeability, wherein a frequency of the RF signal varies in response to the permeability of a bit region in the plurality of bit regions being proximate the spin torque oscillator.2. The apparatus of claim 1 , further comprising a spectrum analyzer connected to the spin transfer oscillator for measuring the frequency and/or amplitude of the RF signal.3. The apparatus of claim 2 , wherein the spectrum analyzer measures changes in the RF signal to indicate a permeability of the region.4. The apparatus of claim 1 , further comprising a superheterodyne receiver to determine a frequency shift in the RF signal indicating a permeability of the bit region.5. The apparatus of claim 1 , further comprising multilevel signaling of n-level bits based on permeability of the bit region.6. The apparatus of claim 1 , further comprising an external magnetic field source for generating a magnetic field proximate the STO.7. The apparatus of claim 6 , wherein the external magnetic field modifies a precession frequency of the spin torque oscillator.8. The apparatus of claim 1 , wherein the spin torque oscillator generates a magnetic field that can be modified by the media and the ...

METHOD AND SYSTEM FOR READING FROM OR WRITING TO MULTIPLE SURFACES OF A DISK

A system includes a management module transferring sectors between an interface or a memory and ports. The management module transfers a first portion of a first sector to or from a first port while transferring to or from a second port a second portion of the first sector or a first portion of a second sector. A first channel module reads from or writes to a first surface of a disk via a first head by transferring the first portion of the first sector to or from a first amplifier module. A second channel module, while the first channel module transfers the first portion of the first sector to or from the first amplifier module, reads from or writes to a second surface of the disk via a second head by transferring to or from a second amplifier module the second portion or the first portion of the second sector. 1. A system comprising:a management module configured to transfer a first sector of data and a second sector of data between (i) an interface or a memory and (ii) a plurality of ports, wherein the interface is connected to a host, wherein the plurality of ports comprise a first port and a second port, and wherein the management module is configured to transfer a first portion of the first sector of data to or from the first port while transferring to or from the second port either (i) a second portion of the first sector of data, or (ii) a first portion of the second sector of data;a first channel module configured to read from or write to a first surface of a disk via a first head by transferring the first portion of the first sector of data to or from a first amplifier module; anda second channel module configured to, while the first channel module transfers the first portion of the first sector of data to or from the first amplifier module, read from or write to a second surface of the disk via a second head by transferring to or from a second amplifier module either (i) the second portion of the first sector of data, or (ii) the first portion of the ...

PARTIAL WRITE SYSTEM

A method and system can be implemented to perform a read-modify-write operation on data recorded in a shingled media format. In one embodiment, a write operation on a band of data stored on a magnetic recording medium is initiated at an intermediate position within the band of data. This is particularly well-suited for data written by a shingled media write operation. 1. A method comprising:initiating a write operation on a band of data stored on a magnetic recording medium at an intermediate position within the band of data.2. The method as claimed in wherein the write operation comprises:utilizing shingled write operations.3. The method as claimed in and further comprising:reading less than the entire band of data from the magnetic recording medium; and then writing over less than the entire band of data on the recording medium.4. The method as claimed in and further comprising:receiving new data for insertion in the band of data;receiving position indication information indicating a target location in the band of data the new data is to be positioned.5. The method as claimed in and further comprising:reading less than the entire band of data from the magnetic recording medium as read data;storing the read data in temporary memory;replacing a portion of the read data in temporary memory with new data so as to form revised data; andwherein the initiating the write operation on the band of data stored on the magnetic recording medium at the intermediate position within the band of data comprises:writing the revised data into the band of data.6. The method as claimed in and further comprising:receiving new data for insertion in the band of data;determining that the new data is to be inserted in the last sector of the band of data;writing the new data over the last sector of the band of data without storing the last sector of data in temporary memory.7. The method as claimed in and further comprising:reading less than the entire band of data from the magnetic ...

DATA MANAGEMENT FOR A DATA STORAGE DEVICE WITH ZONE RELOCATION

Managing data stored on media of a Data Storage Device (DSD) using zone relocation. At least a portion of the media is logically divided into a plurality of zones and zones are identified with access counts greater than or equal to a threshold. The access count for each of the identified zones indicates a number of times data in the zone has been read or written. Data is relocated from at least one zone of the identified zones to at least one destination zone on the media to reduce a data access time between the identified zones. 1. A Data Storage Device (DSD) , comprising:at least one media for storing data; and logically divide at least a portion of the media into a plurality of zones;', 'identify zones of the plurality of zones with access counts greater than or equal to a threshold, wherein the access count for each of the identified zones indicates a number of times data in the zone has been read or written; and', 'relocate data from at least one of the identified zones to at least one destination zone on the media to reduce a data access time between the identified zones., 'a controller configured to2. The DSD of claim 1 , wherein the access count is a random access count indicating a number of times data in the zone has been non-sequentially read or written.3. The DSD of claim 1 , wherein the access count is a sequential access count indicating a number of times data in the zone has been sequentially read or written.4. The DSD of claim 1 , wherein the controller is further configured to update a mapping indicating physical locations for data stored on the media by offsetting physical addresses in the mapping for the relocated data.5. The DSD of claim 1 , wherein the controller is further configured to:logically divide the media into a plurality of blocks with each block having a larger data capacity than individual zones of the plurality of zones;identify a block of the plurality of blocks with a high access count relative to other blocks, wherein the access ...

MAGNETIC TAPE APPARATUS

A magnetic tape apparatus, in which an intensity ratio of peak intensity of diffraction peak of (110) plane with respect to peak intensity of diffraction peak of (114) plane of a hexagonal ferrite crystal structure obtained by XRD analysis of the magnetic layer by In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic tape is 0.65 to 1.00, a reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape, and an extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result. 1. A magnetic tape apparatus comprising:a magnetic tape;a reading element unit; andan extraction unit,wherein the magnetic tape includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support,the magnetic layer includes a servo pattern,the ferromagnetic powder is a hexagonal ferrite powder,an intensity ratio Int(110)/Int(114) of a peak intensity Int(110) of a diffraction peak of a (110) plane with respect to a peak intensity Int(114) of a diffraction peak of a (114) plane of a hexagonal ferrite crystal structure obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0,a vertical squareness ratio of the magnetic tape is 0.65 to 1.00,the reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape,the extraction unit performs a waveform equalization process according to a deviation amount between positions of ...

MAGNETIC RECORDING MEDIUM PROCESSING DEVICE AND METHOD OF GENERATING INTERFERENCE FIELD

A magnetic recording medium processing device may include a magnetic recording medium insertion slot; a medium pathway connected to the magnetic recording medium insertion slot; a magnetic head arranged to face the medium pathway; and an interference magnetic field generating device structured to generate interference magnetic fields outside the magnetic recording medium insertion slot. The interference magnetic field generating device may include a coil, a capacitor, a first power line, a second power line to which a voltage different from that to the first power line is applied, multiple switches structured to switch the connections between the first power line and the second power line of the coil and the capacitor, and a switch control unit structured to control the multiple switches. 1. A magnetic recording medium processing device , comprising:a magnetic recording medium insertion slot;a medium pathway connected to said magnetic recording medium insertion slot;a magnetic head arranged to face said medium pathway; andan interference magnetic field generating device structured to generate interference magnetic fields outside said magnetic recording medium insertion slot; a coil,', 'a capacitor,', 'a first power line,, 'wherein said interference magnetic field generating device comprisesa second power line to which a voltage different from that to said first power line is applied, multiple switches structured to switch the connections between said first power line and said second power line of said coil and said capacitor, anda switch control unit structured to control said multiple switches to first implement a first interference magnetic field generating mode for which said coil and said capacitor are electrically connected in series between said first power line and said second power line and then to implement a second interference magnetic field generating mode for which said coil is oscillated by the charge stored in said capacitor during said first ...

MEDIUM, METHOD OF FABRICATING A MEDIUM, RECORDING SYSTEM AND METHOD OF CONTROLLING A RECORDING SYSTEM

A medium may be provided. The medium includes a servo layer, a data recording layer, and a heat sink layer disposed between the servo layer and the recording layer. 110-. (canceled)11. A recording system , comprising:a first recording head and a second recording head;a medium comprising a data recording layer and a servo layer, wherein the data recording layer is arranged between the recording head and the servo layer;an external energy source;wherein the first recording head and the external energy source are configured to respectively provide a first magnetic field of a first magnetic field strength and external energy for writing on the data recording layer;wherein the second recording head is configured to provide a second magnetic field of a second magnetic field strength for writing on the servo layer;wherein the first magnetic field strength is weaker than the second magnetic field strength.12. The recording system of claim 11 ,wherein the external energy source comprises any one of a group consisting of laser, infrared heating, electrical Joule heating, and injection of hot air.13. The recording system of claim 11 ,wherein the second recording head has a larger dimension than the first recording head.14. The recording system of claim 11 ,wherein the second recording head is configured to write servo information on the servo layer using a shingled writing scheme.15. The recording system of claim 14 ,wherein the second recording head is configured to provide the second magnetic field of the second magnetic field strength for writing on the servo layer.16. The recording system of claim 11 ,wherein the second recording head is configured to write servo information on the servo layer using an energy assisted magnetic recording scheme.17. The recording system of claim 16 ,wherein the second recording head and the external energy source are configured to respectively provide the second magnetic field of the second magnetic field strength and the external energy for ...

SERIAL PORT COMMUNICATION FOR STORAGE DEVICE USING SINGLE BIDIRECTIONAL SERIAL DATA LINE

A method is provided to enable communication between a controller and a preamplifier in a storage device. For example, the method includes implementing a serial port which is configured to transmit digital signals between the controller and the preamplifier over a single bidirectional serial data line. The serial port is controlled to selectively transmit digital signals over the bidirectional serial data line in either a first direction from the controller to the preamplifier or a second direction from the preamplifier to the controller. 1. A method to provide communication between a controller and a preamplifier in a storage device , comprising:implementing a serial port that is configured to transmit digital signals between the controller and the preamplifier over a single bidirectional serial data line; andcontrolling the serial port to selectively transmit digital signals over the bidirectional serial data line in either a first direction from the controller to the preamplifier or a second direction from the preamplifier to the controller.2. The method of claim 1 , wherein controlling the serial port comprises:transmitting a serial bit stream over the bidirectional serial data line from the controller to the preamplifier;generating a clock signal in the preamplifier using a phase-locked loop circuit, wherein the clock signal is generated based on a bit rate of the serial bit stream received by the preamplifier; andusing the clock signal to receive and deserialize the serial bit stream received by the preamplifier.3. The method of claim 2 , wherein controlling the serial port further comprises:transmitting a direction switch control signal over the bidirectional serial data line to the preamplifier; and generating a control signal to suspend phase and frequency adjustments of the phase-locked loop circuit of the preamplifier and maintain a static clock signal output from the phase-locked loop circuit of the preamplifier;', 'assuming control of the bidirectional ...

MANAGING FAR AND NEAR TRACK ERASURE BY DYNAMIC CONTROL OF A WRITE CURRENT PARAMETER OF A MAGNETIC DISK DRIVE

A method may include causing a write head of a magnetic data storage drive to write a first portion of data to a magnetic data storage device of the magnetic data storage drive based at least in part on a first value of at least one parameter of a write current. The method may include updating a value of a write counter and determining whether the value of the write counter is greater than or equal to a threshold write count. The method may also include adjusting the at least one parameter of the write current to a second, different value. The method may further include causing the write head to write a second portion of data to the magnetic data storage device based at least in part on the second value of the at least one parameter of the write current. 1. A method comprising:causing, by a controller of a magnetic data storage drive, a write head of the magnetic data storage drive to write a first portion of data to a magnetic data storage device of the magnetic data storage drive based at least in part on a first value of at least one parameter of a write current;in response to writing the first portion, updating, by the controller, a value of a write counter;determining, by the controller, whether the value of the write counter is greater than or equal to a threshold write count;in response to determining that the value of the write counter is greater than or equal the threshold write count, adjusting, by the controller, the at least one parameter of the write current to a second, different value; andcausing, by the controller, the write head to write a second portion of data to the magnetic data storage device based at least in part on the second value of the at least one parameter of the write current.2. The method of claim 1 , wherein adjusting the at least one parameter of the write current to the second claim 1 , different value comprises adjusting claim 1 , by the controller claim 1 , a rise time from a first duration to a second claim 1 , different ...

MAGNETIC RECORDING AND REPRODUCING DEVICE

According to one embodiment, a magnetic recording and reproducing device includes an output driver, a magnetic head, and a magnetic recording medium. The output driver outputs a recording signal corresponding to input information. The magnetic head includes a coil. A recording current includes the recording signal flows in the coil. Information corresponding to the input information is recorded in the magnetic recording medium. The input information includes first, second, and third information combinations. The first information combination includes first to fourth information. The second information combination includes fifth to eighth information. The third information combination includes ninth to twelfth information. The recording signal changes to an eleventh recording current to correspond to the eleventh information. The recording signal changes to a third recording current to correspond to the third information. An absolute value of the eleventh recording current is greater than an absolute value of the third recording current. 1. A magnetic recording and reproducing device , comprising:an output driver outputting a recording signal corresponding to input information;a magnetic head including a coil, a recording current flowing in the coil, the recording current including the recording signal; anda magnetic recording medium, information being recorded in the magnetic recording medium by the magnetic head, the information corresponding to the input information,the input information including a first information combination, a second information combination, and a third information combination,the first information combination including first to fourth information,the second information being after the first information and being continuous with the first information,the third information being after the second information and being continuous with the second information,the fourth information being after the third information and being continuous with the ...

DETERMINING BIT ASPECT RATIOS FOR PARTIALLY-OVERLAPPING MAGNETIC RECORDING TRACKS

A method involves determining bit aspect ratios for interlaced tracks written to a magnetic recording medium. The interlaced tracks include top tracks that are written partially overlapping with bottom tracks. Isolated test tracks are written at first different bit aspect ratios to determine a top bit aspect ratio that achieves a first target areal density for the isolated test tracks. Test tracks are written at second different bit aspect ratios to determine a bottom bit aspect ratio that achieves a second target areal density for the test tracks. Top test tracks of the test tracks are written at the top bit aspect ratio. The top and bottom bit aspect ratios are selected to subsequently write partially-overlapping tracks on the magnetic recording medium. 1. A method , comprising:writing isolated test tracks to determine a first areal density function for top tracks of a magnetic recording medium, the first areal density function based on write-plus-erase track widths obtained using different first laser powers and first linear bit densities that achieve a first target bit error rate for the isolated test tracks;{'sub': top', 'top, 'selecting a value LDIof the first laser powers and a value BPIof the first linear bit densities that result in a first target value of the areal density function;'}{'sub': top', 'top, 'writing partially-overlapping test tracks to determine a second areal density function of bottom tracks based on squeezed track widths written using different second laser powers and second linear bit densities that achieve a second target bit error rate for bottom test tracks of the partially-overlapping test tracks, top test tracks of the partially-overlapping test tracks being written at LDIand BPI; and'}{'sub': bottom', 'bottom', 'top', 'top', 'bottom', 'bottom, 'selecting a value LDIof the second laser powers and a value BPIof the second linear bit densities that result in a second target value of the second areal density function, the LDI, BPI, LDI, ...

Storage Media Inter-Track interference Cancellation

Described embodiments provide a method of cancelling inter-track interference (ITI) from one or more sectors read from a desired track of a storage medium. A read channel reads sectors in a desired track of the storage medium. A decoder of the read channel decodes the read sectors, and if the read sectors are incorrectly recovered from the storage medium, selected sectors of a first adjacent track and a second adjacent track are read. An ITI canceller of the read channel estimates ITI in the read sectors of the desired track corresponding to the selected sectors of each adjacent track and subtracts the estimated ITI of each adjacent track from the data for the sectors of the desired track, providing updated sector data. The ITI cancelled data is replayed to the decoder, Which decodes the ITT cancelled data and provides the decoded ITI cancelled data as output of the read channel. 1. A storage media controller for cancelling inter-track interference (ITI) in one or more sectors read from a desired track of a storage medium , the media controller comprising:a read channel configured to read one or more sectors in a desired track of the storage medium;an iterative decoder circuit operable to apply a data decoding algorithm to one or more read sectors derived from a desired track of the storage medium to yield a decoded output; the read channel is configured to read selected sectors of a first adjacent track and a second adjacent track;', 'an ITI canceller of the read channel configured to (i) estimate ITI in the one or more read sectors of the desired track corresponding to the selected sectors of the first adjacent track and the second adjacent track, (ii) subtract the estimated ITI of the first adjacent track and the second adjacent track from the data for the one or more sectors of the desired track to provide updated sector data, and (iii) replay the ITI cancelled data to the iterative decoder;', 'the iterative decoder circuit is configured to (i) decode the ITI ...

CURRENT-PERPENDICULAR-TO-PLANE MAGNETO-RESISTANCE EFFECT ELEMENT

The CPPGMR element of the present invention has an orientation layer formed on a substrate to texture a Heusler alloy into a (100) direction, an underlying layer that is an electrode for magneto-resistance measurement stacked on the orientation layer , a lower ferromagnetic layer and an upper ferromagnetic layer each stacked on the underlying layer and made of a Heusler alloy, a spacer layer sandwiched between the lower ferromagnetic layers and the upper ferromagnetic layers , and a cap layer stacked on the upper ferromagnetic layer for surface-protection. This manner makes it possible to provide, inexpensively, an element using a current-perpendicular-to-plane giant magneto-resistance effect (CPPGMR) of a thin film having a trilayered structure of a ferromagnetic metal/a nonmagnetic metal/a ferromagnetic metal, thereby showing excellent performances.

DYNAMIC GAIN CONTROL FOR USE WITH ADAPTIVE EQUALIZERS

According to one embodiment, a system for processing data includes a controller configured to: receive data read from a magnetic storage medium, apply a finite impulse response (FIR) filter to the data to obtain equalized data, and direct the equalized data through either a first FIR gain module or a second FIR gain module to control FIR gain of the equalized data, wherein the first FIR gain module is utilized when reading data in an asynchronous mode, and wherein the second FIR gain module is utilized when reading data in a synchronous mode and a FIR gain value of the second FIR gain module is automatically controlled. Other systems and methods for processing data using dynamic gain control with adaptive equalizers are presented according to more embodiments. 1. A system for processing data , the system comprising a controller configured to:receive data read from a magnetic storage medium;apply a finite impulse response (FIR) filter to the data to obtain equalized data; anddirect the equalized data through either a first FIR gain module or a second FIR gain module to control FIR gain of the equalized data,wherein the first FIR gain module is utilized when reading data in an asynchronous mode, andwherein the second FIR gain module is utilized when reading data in a synchronous mode and a FIR gain value of the second FIR gain module is automatically controlled.2. The system as recited in claim 1 , wherein the controller is further configured to automatically control the FIR gain value in the second FIR gain module using an automated FIR gain control module based on a FIR output from the equalizer and variations in an amplitude of a waveform of the data.3. The system as recited in claim 2 , wherein the automated FIR gain control module comprises logic configured to:receive the FIR output from the equalizer;select at least one error source from a plurality of error sources available to the automated FIR gain control module;calculate the FIR gain value based on error ...

METHOD AND APPARATUS FOR JOINT ADAPTATION OF TWO-/MULTI- DIMENSIONAL EQUALIZER AND PARTIAL RESPONSE TARGET

The present disclosure relates to a method and apparatus for processing of multi-dimensional readback signal from magnetic recording or optical, physical data recording so as to reduce/control Inter Symbol Interference (ISI) and noise within acceptable limits. The method is based on Partial Response Maximum Likelihood (PRML) detection and takes care of time varying channel conditions. In an embodiment, the filter coefficients of both the equalizer and the partial response (PR) target are jointly adapted to account for the channel condition for both separable and non-separable targets thus reducing signal detection complexity. In an aspect, the disclosure provides an apparatus that incorporates an adaptation engine along with the equalizer and the PR target that updates filter coefficients of both the equalizer and the PR target following the formulated mathematical equations. 1. A method for processing of multi-dimensional readback signal to reduce Inter Symbol Interference (ISI) and noise , said method comprising the step of:equalizing the readback signal using a linear equalizer that adapts to varying channel conditions; anddesigning a Partial Response (PR) target for signal detection based on Partial Response Maximum Likelihood (PRML) and the equalizer output, wherein the equalizer and the PR target are jointly adapted.2. The method of claim 1 , wherein the step of equalizing enables handling of channel conditions accounting for one or more time varying factors selected from any or a combination of wear and tear claim 1 , media and temperature variations.3. The method of claim 1 , wherein one or more filter coefficients for the linear equalizer and the PR target are jointly adapted to account for channel condition to help mitigate effects of SNR variations along with ISI reduction/control.4. The method of claim 3 , wherein output of the equalizer is compared with target response to obtain an error that is used to update the one or more filter coefficients.5. The ...

HIGH-RATE REVESE-ORDER RUN-LENGTH-LIMITED CODE

A system and method for encoding a stream of bits with a run-length limited high-rate reverse order encoding schema. According to one embodiment, an RLL encoding block includes a receiver having a precoder operable to receive a stream of N-bits having symbols of M-bits in length, a histogram operable to identify an index symbol of M-bits that does not occur within the received stream of N-bits. It is this index symbol that may be used as the key to encoding a block of symbols so as to ensure unique decodability when RLL decoding. Finally, an encoder operable to perform an exclusive-or operation on each symbol with the next symbol stored in the stream. Such an encoding system only adds one symbol of M bits in length to a block of N bits and still results in a stream of bits sufficient to support high-rate requirements and strict timing loop control. 116-. (canceled)17. A computer system; comprising:a processor;a system bus coupled to the processor and configured to facilitate the transfer of data in the form of a stream of bits;a read/write channel coupled to the system bus, the read/write channel further comprising: a write-channel buffer configured to receive a stream of bits to be sent to a write channel;', 'a write-channel RLL-block configured to determine a unique sequence of bits that is not present in the stream of bits and configured to combine the unique sequence of bits with the stream of bits., 'a write channel, having18. The computer system of further comprising a memory coupled to the system bus.19. The computer system of wherein the read/write channel comprises part of a hard-disk drive system having a hard disk memory configured to be written to via the write channel.20. The computer system of wherein the read/write channel comprises part of a communication channel having a transmitter configured to transmit the stream of bits over a communication channel.21. A method for encoding a stream of bits claim 17 , the method comprising:receiving a stream of ...

Phase error recovery circuitry and method for a magnetic recording device

A recording head is configured to write and read data sectors to and from a recording medium, such as a heat-assisted recording medium. A read channel is coupled to the recording head. Phase-locked loop (PLL) circuitry of the read channel is configured to detect a change in a phase error at a location of the data sector. The phase error change may be indicative of a mode-hop that occurred while writing the data sector to the medium. The PLL circuitry is configured to determine a phase offset using the phase error. A controller is configured to effect re-reading of the data sector location using the phase offset to recover the data sector location.

MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING APPARATUS

According to an embodiment, a magnetic recording head includes a main magnetic pole and a spin torque oscillator. The spin torque oscillator includes a first perpendicular free layer, a second perpendicular free layer, and a first spacer layer, each of the first perpendicular free layer and the second perpendicular free layer including a magnetic anisotropy axis in a direction perpendicular to a film plane of the spin torque oscillator. An effective perpendicular magnetic anisotropy magnetic field of the first perpendicular free layer is smaller than an effective perpendicular magnetic anisotropy magnetic field of the second perpendicular free layer, and a current is applied from the first perpendicular free layer side to the second perpendicular free layer side. 1. A magnetic recording head comprising:a main magnetic pole which generates a recording magnetic field; anda spin torque oscillator which generates a high frequency magnetic field, the spin torque oscillator comprising a pair of electrode layers and a multilayer film provided between the pair of electrode layers, the multilayer film comprising a first perpendicular free layer in which magnetization is rotatable, a second perpendicular free layer in which magnetization is rotatable, and a first spacer layer provided between the first perpendicular free layer and the second perpendicular free layer, each of the first perpendicular free layer and the second perpendicular free layer including a magnetic anisotropy axis in a direction perpendicular to a film plane of the spin torque oscillator, wherein an effective perpendicular magnetic anisotropy magnetic field of the first perpendicular free layer is smaller than an effective perpendicular magnetic anisotropy magnetic field of the second perpendicular free layer, and a current is applied from the first perpendicular free layer side to the second perpendicular free layer side through the pair of electrode layers.2. The magnetic recording head according to ...

Dual Pass Perpendicular Magnetic Recording

Dual Pass Perpendicular Magnetic Recording is an invention to increase the storage capacity of disk drives and provides faster data transfer when reading data from a disk drive operating in this mode. By using two passes of the recording head to write a data track, more magnetic states are created than in conventional or shingled magnetic recording. This allows a higher storage capacity to be achieved.

DETECTION OF OPEN WRITE HEADS AND/OR CABLES IN TAPE DRIVES

A computer-implemented method, according to one embodiment, includes: receiving a first output signal from a write driver, the write driver having an operating voltage applied thereto, receiving a second output signal from a comparator circuit, the comparator circuit having a reference voltage applied thereto, comparing a voltage of the first output signal with a voltage of the second output signal, and detecting a high resistance condition in response to determining that the voltage of the first output signal is less than the voltage of the second output signal. According to the present embodiment, the high resistance condition indicates open and/or partially open circuitry in the write driver. Moreover, the operating voltage is equal to the reference voltage. Other systems, methods, and computer program products are described in additional embodiments. 1. A computer-implemented method , comprising:receiving a first output signal from a write driver, the write driver having an operating voltage applied thereto;receiving a second output signal from a comparator circuit, the comparator circuit having a reference voltage applied thereto;comparing a voltage of the first output signal with a voltage of the second output signal; anddetecting a high resistance condition in response to determining that the voltage of the first output signal is less than the voltage of the second output signal,wherein the high resistance condition indicates open and/or partially open circuitry in the write driver,wherein the operating voltage is equal to the reference voltage.2. The method as recited in claim 1 , wherein the write driver and the comparator circuit are formed on a common chip.3. The method as recited in claim 1 , wherein the comparing of the first and second output voltages is not performed while a magnetic tape is adjacent a write head coupled to the write driver.4. The method as recited in claim 1 , wherein the comparing is performed by a comparator circuit configured to ...

CONTROLLING A TAPE SPEED TO MANAGE A TAPE DRIVE BUFFER

Provided are a storage device, method, and program for controlling a tape speed to manage a tape drive buffer. A tape speed is increased from a current tape speed to a target tape speed on a predetermined speed-change timing to control the reading or writing of data between the buffer and the tape medium.

MAGNETIC DISK DEVICE AND WRITE PROCESSING METHOD

According to one embodiment, a magnetic disk device includes a disk, a head including a first write head and a second write head configured to write data to the disk and a read head configured to read data from the disk, and a controller configured to write write data to a first area of the disk with the first write head and to overwrite the write data written with the first write head in the first area with the second write head. 1. A magnetic disk device comprising:a disk;a head including a first write head and a second write head configured to write data to the disk and a read head configured to read data from the disk; anda controller configured to write write data to a first area of the disk with the first write head and to overwrite the write data written with the first write head in the first area with the second write head.2. The magnetic disk device of claim 1 , wherein the controller adjusts a first timing to overwrite the write data written with the first write head with the second write head based on a correction value.3. The magnetic disk device of claim 2 , wherein the controller calculates the correction value based on a first read waveform from reading of the write data written with the first write head and a second read waveform from reading the write data overwritten with the second write head.4. The magnetic disk device of claim 2 , wherein the controller calculates the correction value based on a gap between the first write head and the second write head and a rotation speed of the disk.5. The magnetic disk device of claim 1 , wherein the first write head is disposed between the read head and the second write head claim 1 , and a first width of the first write head in the radius direction is less than a second width of the second write head in the radius direction.6. The magnetic disk device of claim 5 , wherein the controller performs claim 5 , if the head is inclined to a first direction of the radius direction of the disk claim 5 , shingled ...

METHOD AND SYSTEM FOR PREVENTING UNRELIABLE DATA OPERATIONS AT COLD TEMPERATURES

Systems and methods for reducing problems and disadvantages associated with protecting data during cold excursions are provided. A method for preventing unreliable data operations at cold temperatures may include determining whether a first internal temperature of a hard disk drive (HDD) is below a threshold temperature. The method may also include initiating an artificial seek operation if the first internal temperature is below the threshold temperature. 1. A method for preventing unreliable data operations at cold temperatures comprising:determining whether a first internal temperature of a hard disk drive (HDD) is below a threshold temperature; andinitiating an artificial seek operation if the first internal temperature is below the threshold temperature.2. The method of claim 1 , further comprising sampling a second internal temperature of the HDD following a pre-defined time interval.3. The method of claim 2 , further comprising pausing a read/write operation if the second internal temperature of the HDD is below the threshold temperature.4. The method of claim 3 , further comprising proceeding with the read/write operation if the second internal temperature of the HDD is above the threshold temperature.5. The method of claim 1 , further comprising spinning the HDD up to a target revolutions per minute (RPM).6. The method of claim 1 , wherein the artificial seek operation comprises one of a random seek claim 1 , a butterfly seek claim 1 , a ⅓ stroke seek claim 1 , and a sequential seek.7. The method of claim 1 , wherein the threshold temperature is provided by a user.8. The method of claim 2 , wherein the pre-defined time interval is substantially based on an event.9. The method of claim 2 , wherein the pre-defined time interval is provided by a user.10. A hard disk drive (HDD) comprising:a temperature sensor configured to transmit a signal corresponding to a first internal temperature; anda component configured to perform an artificial seek operation if the ...

Thermally assisted magnetic recording medium and magnetic recording and reproducing apparatus

A thermally assisted magnetic recording medium ( 1 ) includes a substrate ( 101 ), an underlayer ( 3 ) that is formed above the substrate ( 101 ), and a magnetic layer ( 107 ) that is formed on the underlayer ( 3 ) and contains an alloy having an L1 0 structure as a main component. The underlayer ( 3 ) is formed by continuously laminating a first underlayer ( 104 ) having a BCC structure with a lattice constant that is 0.302 to 0.332 nm, a second underlayer ( 105 ) that has a NaCl structure including C, and a third underlayer ( 106 ) that is composed of MgO.

MAGNETIC HEAD AND MAGNETIC RECORDING DEVICE

According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic pole and the first magnetic layer, a third magnetic layer provided between the first magnetic pole and the second magnetic layer, a first nonmagnetic layer provided between the second and first magnetic layers, a second nonmagnetic layer provided between the third and second magnetic layers, and a third nonmagnetic layer provided between the first magnetic pole and the third magnetic layer. The second magnetic layer includes first and second magnetic regions. The second magnetic region is between the second nonmagnetic layer and the first magnetic region. The first magnetic region includes a first element. The second magnetic region includes the first element, and a second element.

METHOD AND SYSTEM FOR ESTIMATING THE POSITION ERROR SIGNAL (PES) METRIC FOR A MAGNETIC STORAGE SYSTEM

A method and system for estimating the position error signal (PES) metric for a magnetic storage system. The method comprises the steps of reading multiple readback tracks from a storage medium of the magnetic storage system using respective readers of a multiple reader head positioned at or near a data track of interest; employing an adaptive SMR equalizer to equalize the signals from the multiple read head; and extracting information from the adaptive SMR equalizer sub-filters as an estimate of the PES metric. 1. A method of estimating the position error signal (PES) metric for a magnetic storage system , the method comprising the steps of:reading multiple readback tracks from a storage medium of the magnetic storage system using respective readers of a multiple reader head positioned at or near a data track of interest;employing an adaptive SMR equalizer to equalize the signals from the multiple read head; andextracting information from the adaptive SMR equalizer sub-filters as an estimate of the PES metric.2. The method as claimed in claim 1 , wherein extracting the information comprises calculating energies of the respective equalizer sub-filters.3. The method as claimed in claim 2 , further comprising calculating differences in the energies of the respective equalizer sub-filters.4. The method as claimed in claim 3 , further comprising normalizing the calculated differences in the energies of the respective equalizer sub-filters.5. The method as claimed in claim 4 , wherein the normalizing comprises dividing the calculated differences in the energies of the respective equalizer sub-filters by the sum of the energies.6. The method as claimed in claim 1 , wherein the adaptive SMR equalizer is based on any of a group of adaptive filtering algorithms including claim 1 , but not limited to the least mean square algorithm (LMS) claim 1 , the variable step-size least mean square (VSLMS) algorithm claim 1 , the frequency based LMS algorithm claim 1 , and the ...

MAGNETIC DISK DEVICE AND RECORDING HEAD CONTROL METHOD

According to one embodiment, a magnetic disk device conforming to perpendicular magnetic recording includes a magnetic disk, a recording head, and a controller. The head includes a main magnetic pole, a return magnetic pole, a recording coil, and a conductive member in which end surfaces are connected to opposed surfaces of a write gap which is opposed to a distal portion of the main magnetic pole and a distal portion of the return magnetic pole, and a resistance value varies. The controller applies a current to the recording coil to excite the magnetic flux in the recording operation, and applies a current at a constant voltage to the magnetic circuit via the comductive member. 1. A magnetic disk device comprising:a magnetic disk having a recording layer conforming to perpendicular magnetic recording;a recording head which generates a perpendicular recording magnetic field to be applied to the recording layer; anda controller which controls a recording operation and a non-recording operation of the recording head, whereinthe recording head includes:a main magnetic pole which generates the perpendicular recording magnetic field;a return magnetic pole which returns a magnetic flux from the main magnetic pole and forms a magnetic circuit in cooperation with the main magnetic pole;a recording coil which excites the magnetic flux in the magnetic circuit formed of the main magnetic pole and the return magnetic pole; anda conductive member in which end surfaces are connected to opposed surfaces of a write gap which is opposed to a distal portion of the main magnetic pole and a distal portion of the return magnetic pole, and a resistance value varies between the recording operation and the non-recording operation, andthe controller includes:a constant voltage supply source which applies a current at a constant voltage to the magnetic circuit formed in the main magnetic pole and the return magnetic pole via the conductive member; anda current supply source which applies a ...

Systems and Methods for Multi-Level Encoding and Decoding

A storage system includes a storage medium operable to maintain a data set, a read/write head assembly operable to write the data set to the storage medium and to read the data set from the storage medium, a multi-level encoder operable to encode the data set at a plurality of different code rates before it is written to the storage medium, and a multi-level decoder operable to decode the data set retrieved from the storage medium and to apply decoded values encoded at a lower code rate when decoding values encoded at a higher code rate. 1. A storage system comprising:a storage medium operable to maintain a data set;a read/write head assembly operable to write the data set to the storage medium and to read the data set from the storage medium;a multi-level encoder operable to encode the data set at a plurality of different code rates before it is written to the storage medium; anda multi-level decoder operable to decode the data set retrieved from the storage medium and to apply decoded values encoded at a lower code rate when decoding values encoded at a higher code rate, wherein the multi-level encoder is operable to encode the data set at a plurality of different code rates such that symbols encoded at different code rates in the data set are interleaved on the storage medium.2. (canceled)3. The storage system of claim 1 , wherein each symbol in the data set maintained on the storage medium is recorded adjacent at least one other symbol in the data set encoded at a different one of the plurality of code rates.4. The storage system of claim 1 , wherein applying decoded values encoded at a lower code rate when decoding values encoded at a higher code rate reduces inter-track interference.5. The storage system of claim 1 , wherein the multi-level encoder comprises a serial to parallel converter operable to divide the data set into a plurality of data segments to be encoded at the different code rates.6. The storage system of claim 1 , wherein the multi-level encoder ...

Adaptive Pattern Detection for Pattern-Dependent Write Current Control in a Magnetic Recording System

The disclosure is directed to a system and method of a system and method for determining fundamental bit cell duration of a data record, which can be used for pattern-dependent write (PDW) current control. According to various embodiments of the disclosure, at least a first portion of a data record is fed through a plurality of delay units. A binary output of each delay unit is stored in at least one register when the delay units have received the first portion of the data record. The register contents are then decoded to determine fundamental bit cell duration of the data record based upon the stored binary outputs. 1. A system for determining fundamental bit cell duration of a data record , comprising:a plurality of delay units configured to receive at least a first portion of a data record;at least one register configured to store a binary output of each delay unit of the plurality of delay units when the plurality of delay units have received the first portion of the data record; anda decoder configured to determine a fundamental bit cell duration based upon the stored binary outputs of the plurality of delay units.2. The system of claim 1 , wherein the first portion of the data record includes at least a portion of a preamble of the data record.3. The system of claim 2 , wherein the preamble of the data record includes bit cells with uniform durations.4. The system of claim 1 , wherein the first portion of the data record includes a bit cell with a duration that is a multiple of the fundamental bit cell duration.5. The system of claim 4 , wherein the fundamental bit cell duration is half of the duration of the bit cell of the first portion of the data record.6. The system of claim 1 , wherein each delay unit of the plurality of delay units is configured to provide a delay of approximately t claim 1 , where t is a substantially fixed duration.7. The system of claim 6 , wherein the decoder is configured to determine the fundamental bit duration as a function of t ...

DATA MIGRATION FOR DATA STORAGE DEVICE

Migration of data in a data storage device (DSD). A spindle motor of the DSD is controlled to rotate a disk of the DSD to perform at least one operation on the disk and an operational activity level is determined for performing the at least one operation. It is determined whether the operational activity level is greater than a target level, and if it is determined that the operational activity level is not greater than the target level, data is transferred between a solid state memory of the DSD and the disk while the disk rotates. 1. A data storage device (DSD) , comprising:a disk for storing data;a spindle motor for rotating the disk;a solid state memory for storing data; and control the spindle motor to rotate the disk to perform at least one operation on the disk;', 'determine an operational activity level for performing the at least one operation;', 'determine whether the operational activity level is greater than a target level; and', 'if it is determined that the operational activity level is not greater than the target level, transfer data between the solid state memory and the disk while the disk rotates., 'a controller configured to2. The DSD of claim 1 , wherein the operational activity level represents a number of commands queued for performance on the disk.3. The DSD of claim 1 , wherein the controller is further configured to set the target level based on a performance limit for performing operations on the disk.4. The DSD of claim 1 , wherein the data transferred between the solid state memory and the disk includes dirty data transferred from the solid state memory to the disk claim 1 , the dirty data including data that is most recently written for a logical address and that can be used to update the disk by writing the dirty data to the disk for the logical address.5. The DSD of claim 1 , wherein the data transferred between the solid state memory and the disk includes at least one of frequently accessed data and high priority data transferred from ...

Zoned Block Command To Stream Command Translator

A method for performing an operation of a memory arrangement, comprising receiving a command at a layer of a computer system, determining if the command received is one of a first command type or a second command type, determining a type of command that is able to be received and is capable of operation of the memory arrangement, comparing the type of command capable of operation of the memory arrangement and the received command at the layer, and converting the command received at the layer to a command type capable of operation of the memory arrangement when the type of command received at the layer is different than type of command that is able to be received and is capable of operation of the memory arrangement. 1. A computer system , comprising: receive a command at a layer of the computer system; and', 'convert the command received at the layer to a command type capable of operation in the memory arrangement when the type of command received at the layer is different than a type of command that is able to be received and is capable of operation in the memory arrangement, wherein the converting comprises converting a zone block command to a stream command., 'a memory arrangement, wherein the computer system is configured to2. The computer system of claim 1 , wherein the layer of the computer system is within a host system.3. The computer system of claim 1 , wherein the layer of the computer system is within an SAS expander.4. The computer system of claim 1 , wherein the layer of the computer system is in the memory arrangement.5. The computer system of claim 1 , wherein the layer is a z-stream translator.6. The computer system of claim 5 , wherein the z-stream translator comprises a write zone manager.7. The computer system of claim 1 , wherein the memory arrangement is a solid state drive.8. The computer system of claim 1 , wherein the computer system is further configured to:transmit the command type capable of operation for the memory arrangement to the ...

High Frequency Data Writer Field Generator Device

A data writing device may be constructed and operated with at least a data writer that has at least a write pole and a magnetic feature. A controller may selectively activate the magnetic feature to magnetically oscillate and produce a radio frequency signal proximal the write pole on an air bearing surface (ABS). 1. An apparatus comprising a data writer comprising a write pole separated from a magnetic feature by a magnetic shield on an air bearing surface (ABS) , a controller configured to heat and cool the magnetic feature to magnetically oscillate the magnetic shield to produce a radio frequency signal proximal the write pole on the ABS.2. The apparatus of claim 1 , wherein the magnetic feature comprises a conductive wire.3. The apparatus of claim 12 , wherein the second magnetic feature comprises a shunt.4. The apparatus of claim 3 , wherein the shunt comprises a ferromagnetic material doped with a non-magnetic metal.5. The apparatus of claim 3 , wherein the shunt comprises gadolinium.6. The apparatus of claim 1 , wherein the magnetic feature is positioned proximal a leading edge of the write pole on the ABS.7. The apparatus of claim 1 , wherein the magnetic shield is disposed between the magnetic feature and the ABS.8. The apparatus of claim 7 , wherein the magnetic feature is physically separated from the magnetic shield.9. The apparatus of claim 1 , wherein the magnetic feature is positioned proximal a trailing side of the write pole.10. The apparatus of claim 1 , wherein the radio frequency is a microwave frequency.11. The apparatus of claim 1 , wherein the magnetic shield comprises a material having a 2.4 T magnetic saturation.12. An apparatus comprising a data writer comprising a write pole claim 1 , first magnetic feature claim 1 , and second magnetic feature claim 1 , the first magnetic feature separated from the write pole by a first magnetic shield on an air bearing surface (ABS) claim 1 , the second magnetic feature separated from the write pole and ...

DETERMINING OSCILLATION CHARACTERISTIC FOR HIGH-FREQUENCY ASSISTED MAGNETIC RECORDING DEVICE

A magnetic disk device according to an embodiment includes a magnetic head including a write head with a high-frequency oscillator and a read head, a recording medium, a driving unit configured to moves the magnetic head on the recording medium, a measuring unit configured to obtain a first read signal with no current or a smaller current and a second read signal with a normal current supplied in the normal writing operation, a comparison unit configured to calculate comparative data indicating a comparison result between the first and second read signals, and a determination unit configured to determine an oscillation characteristic from the comparative data. 1. A magnetic disk device comprising:a magnetic head including a write head with a high-frequency oscillator and a read head;a recording medium to and from which data is written and read by the magnetic head;a driving unit configured to move the magnetic head on the recording medium;a measuring unit configured to obtain a first read signal and a second read signal, the first read signal being obtained by reading a first data pattern written when no current is supplied to the high-frequency oscillator or a smaller current than in a writing operation to the recording medium is supplied to the high-frequency oscillator, the second read signal being obtained by reading a second data pattern written when a current supplied in the normal writing operation to the recording medium is supplied to the high-frequency oscillator;a comparison unit configured to calculate comparative data indicative of a comparison result between the first and second read signals; anda determination unit configured to determine an oscillation characteristic of the high-frequency oscillator from the comparative data.2. The magnetic disk device of claim 1 , further comprising:a heater provided in the magnetic head, and to generate heat for changing floating amount of the magnetic head when a current is supplied thereto,wherein the measuring ...

APPARATUS WITH FIRST AND SECOND CLOSE POINTS ON MEDIA-FACING SURFACE OF MAGNETIC HEAD

A magnetic head includes a read transducer and a write transducer at a media-facing surface of the magnetic head. The magnetic head includes at least one heater that causes heat deformation at the media-facing surface in response to different first and second energizing currents. The first energizing current results in a first close point between the media-facing surface and a recording medium. The second energizing current results in a second close point between the media-facing surface and the recording medium. The second close point is at a different location in the media-facing surface than the first close point. 1. A method comprising:applying a first energizing current to a heater of a magnetic head responsive to entering a first operational mode of the magnetic head, the first energizing current resulting in a first close point between a media-facing surface of the magnetic head and a recording medium, the first close point proximate to a read transducer of the magnetic head; andapplying a different, second energizing current to the heater responsive to entering a second operational mode of the magnetic head, the second energizing current resulting in a second close point between the media-facing surface and the recording medium, the second close point proximate to a contact pad disposed at the media-facing surface between the read transducer and a write transducer of the magnetic head.2. The method of claim 1 , wherein the first and second operational modes comprise respective read and write modes during which the respective read and write transducers of the magnetic head are used for reading and writing to the recording medium.3. The method of claim 2 , further comprising energizing the write transducer during the write mode claim 2 , wherein the energized write transducer contributes to the heat deformation at the media-facing surface and influences the respective first and second close points.4. The method of claim 3 , further comprising energizing a ...

METHODS FOR READING DATA FROM A STORAGE MEDIUM USING A READER AND STORAGE DEVICES

According to various embodiments, a method for reading data from a storage medium using a reader may be provided. The method may include: reading a first signal with a reader head of the reader at a first position of the storage medium; reading a second signal with a reader head of the reader at a second position of the storage medium; and determining data stored at a pre-determined position of the storage medium based on the first signal and based on the second signal. 1. A method for reading data from a storage medium using a reader , the method comprising:reading a first signal with a reader head of the reader at a first position of the storage medium;reading a second signal with a reader head of the reader at a second position of the storage medium; anddetermining data stored at a pre-determined position of the storage medium based on the first signal and based on the second signal.2. The method of claim 1 ,wherein the storage medium comprises a plurality of tracks, each track having a width smaller than a width of a reader head of the reader.3. The method of claim 1 ,wherein for at least one of the first position or the second position a reader head of the reader covers a first track and a second track.4. The method of claim 3 ,wherein the pre-determined position comprises one of a pre-determined position on the first track or a pre-determined position on the second track.5. The method of claim 3 ,wherein the first track and the second track are adjacent.6. The method of claim 1 , further comprising:reading a plurality of signals, wherein for each signal a reader head of the reader is at a different position of the storage medium; anddetermining data stored at the pre-determined position of the storage medium based on the plurality of signals.7. The method of claim 1 , further comprising:reading a frequency burst signal with a reader head of the reader at a position of the storage medium comprising a frequency burst provided before a data drack on the storage ...

MAGNETIC DISK DEVICE AND WRITE CONTROL METHOD

A magnetic disk device according to an embodiment includes a disk including a plurality of tracks, a head configured to write and read data to and from the disk, and a controller configured to control an off-track of the head, which occurs when data is written to one track included in the plurality of tracks, within an allowable range of an amount of the off-track, which is set based on a count value of at least another track other than the one track. 1. A magnetic disk device comprising:a disk including a plurality of tracks;a head configured to write and read data to and from the disk; anda controller configured to control an off-track of the head, which occurs when data is written to one track included in the plurality of tracks, within an allowable range of an amount of the off-track, which is set based on a count value of at least another track other than the one track.2. The magnetic disk device of claim 1 , wherein:the controller sets a first allowable range of an amount of an off-track to an inner side of the one track in a radial direction of the disk, based on a first count value of a first track of a plurality of tracks on the inner side of the one track;sets a second allowable range of an amount of an off-track to an outer side of the one track in the radial direction of the disk, based on a second count value of a second track of a plurality of tracks on the outer side of the one track; andcontrols an off-track to the inner side from a center of the one track within the first allowable range and an off-track to the outer side from the center of the one track within the second allowable range.3. The magnetic disk device of claim 2 , wherein the first track is a track adjacent to the inner side of the one track and the second track is a track adjacent to the outer side of the one track.4. The magnetic disk device of claim 3 , wherein:the controller stops write to the one track if the amount of the off-track exceeds the first allowable range or the second ...

DISK DEVICE HAVING CONVENTIONAL MAGNETIC RECORDING REGION AND SHINGLED MAGNETIC RECORDING REGION OF DIFFERENT LINEAR DENSITY

According to one embodiment, a magnetic disk device includes a disk, a head which writes data to the disk and reads data from the disk, and a controller which executes, in a first region segmented in a radial direction of the disk, at least one of conventional recording processing which writes a plurality of tracks with a space in between in the radial direction at a first linear recording density and shingled recording processing which writes a plurality of tracks on top of one another in the radial direction at a second linear recording density which is less than or equal to the first linear recording density. 1. A magnetic disk device comprising:a disk;a head which writes data to the disk and reads data from the disk; anda controller which executes, in a first region segmented in a radial direction of the disk, at least one of conventional recording processing which writes a plurality of tracks with a space in between in the radial direction at a first linear recording density and shingled recording processing which writes a plurality of tracks on top of one another in the radial direction at a second linear recording density which is less than or equal to the first linear recording density, whereinthe controller executes the shingled recording processing at the second linear recording density and at a track density at which a product of the second linear recording density and the track density becomes maximized in the first region.2. (canceled)3. The magnetic disk device of claim 1 , wherein a first recording density at which a plurality of tracks are written with a space in between in the radial direction at the first linear recording density in the first region is less than a second recording density at which a plurality of tracks are written on top of one another in the radial direction at the second linear recording density in the first region by 10% to 23%.4. The magnetic disk device of claim 1 , wherein the controller executes the conventional recording ...

SELECTABLE READ MODES FOR A TWO DIMENSIONAL MAGNETIC RECORDING SYSTEM

Two or more read modes of a data storage system and device are defined. The data storage device is capable of concurrently reading from two or more tracks using two or more read transducers. The read modes utilize different numbers of the two or more read transducers while reading data. The tread modes are selected based on an operating condition of the data storage system or device. 1. A system comprising:a plurality of data storage devices each comprising two or more transducers capable of concurrently reading from tracks of a recording medium in a two-dimensional magnetic recording configuration; anda system controller coupled to the data storage devices and configured to define two or more read modes affecting at least a subset of the data storage devices, the read modes utilizing different numbers of the two or more read transducers while reading data, and configured to select from the read modes based on an operating condition of the system.2. The system of claim 1 , wherein the system controller selects from the read modes via a command descriptor block of a host interface protocol used for communicating with the data storage devices.3. The system of claim 1 , wherein the operating condition comprises a target power consumption of the system or a target operating temperature of the system.4. The system of claim 1 , wherein the operating condition comprises a RAID rebuild or drive replication of the system such that maximum performance is desired and the read mode with a greater number of activated read transducers is utilized.5. The system of ; wherein a first of the read modes comprises using one of the transducers claim 1 , and a second of the read modes comprises using at least two of the transducers.6. The system of claim 5 , wherein the first mode utilizes one-dimensional detection claim 5 , and the second mode utilizes two-dimensional detection.7. The system of claim 5 , wherein the tracks comprise shingled tracks claim 5 , and the second mode comprises ...

MAGNETIC DISK DEVICE AND WRITE METHOD

A magnetic disk device includes a disk, a head configured to write data on the disk based on a write current, and a controller configured to determine whether a write error occurs when data is written on the disk, based on a change in a heating value of the head, and upon determining that the write error occurs, read the data written on the disk. 1. A magnetic disk device comprising:a disk;a head configured to write data on the disk based on a write current; anda controller configured to determine whether a write error occurs when data is written on the disk, based on a change in a heating value of the head, and upon determining that the write error occurs, read the data written on the disk.2. The magnetic disk device according to claim 1 , whereinthe head includes a write coil to which the write current is supplied, and the heating value of the head changes in accordance with a resistance value of the write coil, andthe controller determines that the write error occurs when it is determined that a resistance value of the write coil is less than a threshold value.3. The magnetic disk device according to claim 2 , wherein the controller sets the threshold value as a resistance value of the write coil at a previous writing time.4. The magnetic disk device according to claim 2 , further comprising:an integrated circuit configured to output the write current of which amplitude is modulated based on a clock signal and write data, to the head, and including a measurement unit that measures a resistance value of the write coil which corresponds to a change in the write current, whereinwhen the measured resistance value is less than the threshold value, the controller determines that the write error occurs and reads the data written on the disk.5. The magnetic disk device according to claim 4 , wherein when the measured resistance value is less than the threshold value claim 4 , the controller adjusts phases of the clock signal and the write data.6. The magnetic disk device ...

DISK APPARATUS AND HEAD APPARATUS

A disk apparatus includes a disk, a head, a circuit board, and an abnormality detection circuit. The head includes a plurality of loads, including at least a first load and a second load, associated with writing or reading of data to or from the disk, and a plurality of head terminals corresponding to and connected to the plurality of loads, respectively. The circuit board includes board terminals corresponding to and connected to the plurality of head terminals, respectively, and a preamplifier that applies a voltage to the loads via the plurality of board terminals during writing or reading of the data to or from the disk. The abnormality detection circuit detects a short-circuit between a first board terminal, which is the board terminal connected to the head terminal of the first load, and a second board terminal, which is the board terminal connected to the head terminal of the second load. 1. A disk apparatus comprising:a disk;a magnetic head including a plurality of loads, including at least a first load and a second load, and a plurality of head terminals corresponding to and connected to the plurality of loads, respectively;a circuit board including a plurality of board terminals corresponding to and connected to the plurality of head terminals, respectively, and a preamplifier configured to apply a voltage to the loads via the plurality of board terminals, the plurality of board terminals including a first board terminal and a second board terminal that are connected to the first load via at least part of the head terminals, and a third board terminal that is connected to the second load via at least part of the head terminals and not connected to the first load;a first abnormality detection circuit configured to detect a short-circuit between the first board terminal and the second board terminal; anda second abnormality detection circuit configured to detect a short-circuit between the second board terminal and the third board terminal.2. The disk ...

DISK STORAGE APPARATUS AND METHOD FOR SERVO CONTROLLING

According to one embodiment, a disk storage apparatus includes an interrupt controller and a servo controller. The interrupt controller determines whether or not to carry out servo interrupt processing and holds a number of negative results of the determination. The servo controller includes an internal model configured to calculate an estimated current position of the head. The servo controller corrects a state of the internal model based on the number of negative results of the determination and performs head positioning control based on a result of a calculation of the internal model, if the result of the determination by the interrupt controller is affirmative. 1. A disk storage apparatus comprising:an interrupt controller configured to determine whether or not to carry out servo interrupt processing and to hold a number of negative results of the determination; anda servo controller comprising an internal model configured to follow a detected position of a head to calculate an estimated current position which is a position error with respect to a target position of the head,wherein the servo controller is configured to correct a state of the internal model based on the number of negative results of the determination and perform head positioning control based on a result of a calculation of the internal model, if the result of the determination by the interrupt controller is affirmative.2. The disk storage apparatus of claim 1 , further comprising:a command processor configured to inhibit the servo interrupt processing and to preferentially carry out command processing,wherein the interrupt controller is configured to determine whether or not to carry out the servo interrupt processing based on a state of execution of the command processing in response to a servo interrupt request at each sampling point of time, and count and hold the number of negative results of the determination corresponding to an elapsed time of execution of the command processing in ...

System and Method for Monitoring Preamble Signal Quality

The disclosure is directed to a system and method of determining signal quality based upon at least one of: a comparison of energy content of the signal to a threshold energy content, a comparison of energy content of the fundamental harmonic of the signal to a specified percentage of the energy content of the signal, and a comparison of a difference between phase of the signal and a target phase to a threshold phase difference. 1. A system for analyzing signal quality , the system comprising at least one processor communicatively coupled to a storage medium , the at least one processor being configured to:receive a signal from the storage medium;determine an energy content of the signal;determine an energy content of a fundamental harmonic of the signal;determine a phase of the signal; anddetermine a quality of the signal based upon at least one of: the energy content of the signal, the energy content of the fundamental harmonic of the signal, and the phase of the signal.2. The system of claim 1 , wherein the at least one processor is further configured to:square digital samples derived from the signal; anddetermine the energy content of the signal by summing the squares of the digital samples.3. The system of claim 2 , wherein the digital samples comprise normalized digital samples.4. The system of claim 1 , wherein the at least one processor is further configured to:determine sine and cosine components of a discrete Fourier transform of the signal; anddetermine the energy content of the fundamental harmonic of the signal by summing a square of the sine component and a square of the cosine component.5. The system of claim 1 , wherein the at least one processor is further configured to:determine the phase of the signal utilizing an output of a bandpass filter.6. The system of claim 5 , wherein the bandpass filter comprises an nT bandpass filter claim 5 , where n is an integer defined by the fundamental harmonic of the signal.7. The system of claim 1 , wherein the ...

DETECTING TRACK INFORMATION FROM OVERLAPPING SIGNALS READ FROM A DATA STORAGE MEDIUM

Detecting track information involves receiving first and second overlapping track signals from first and second read elements that read first and second tracks from a data storage medium. Information of the first and second tracks is estimated using the respective first and second track signals. An improved information estimate of the first track is obtained using the first track signal and the estimated information of the second track, and an improved information estimate of the second track is obtained using the second track signal and the estimated information of the first track. First and second track data are decoded using the respective improved information estimates of the first and second tracks. 1. A method comprising:receiving first and second overlapping track signals from first and second read elements that read first and second tracks from a data storage medium;estimating information of the first and second tracks using the respective first and second track signals;obtaining an improved information estimate of the first track using the first track signal and the estimated information of the second track;obtaining an improved information estimate of the second track using the second track signal and the estimated information of the first track; anddecoding first and second track data using the respective improved information estimates of the first and second tracks.2. The method of claim 1 , wherein the first and second read elements concurrently read first and second tracks from the data storage medium.3. The method of claim 1 , wherein the operations of obtaining the improved information estimates of the first and second tracks are performed in parallel.4. The method of claim 1 , wherein the operations of obtaining the improved information estimate of the first and second tracks are iteratively repeated claim 1 , wherein the improved information estimate of the first and second tracks from one iteration are used as the respective estimated information ...

Non-Binary Layered Low Density Parity Check Decoder

A non-binary layered low density parity check decoder includes a variable node processor operable to generate variable node to check node messages and to calculate perceived values based on normalized check node to variable node messages and on normalized decoder inputs, and to output normalized decoded values, and a check node processor operable to generate the check node to variable node messages based on normalized variable node to check node messages. 1. A low density parity check decoder comprising:a variable node processor operable to generate variable node to check node messages and to calculate perceived values based on normalized check node to variable node messages and on normalized decoder inputs, and to output normalized decoded values; anda check node processor operable to generate the check node to variable node messages based on normalized variable node to check node messages, wherein the variable node processor and check node processor are operable to perform layered multi-level decoding.2. The decoder of claim 1 , wherein the normalized decoder inputs and normalized decoded values comprise hard decisions and soft data claim 1 , wherein the soft data is normalized to a likelihood of the corresponding hard decision.3. The decoder of claim 1 , wherein the variable node processor comprises a format conversion circuit operable to convert the normalized decoder inputs to a non-normalized format.4. The decoder of claim 3 , wherein the non-normalized format of a likelihood value for a symbol comprises probabilities for each element of a Galois Field that the symbol has a value of the corresponding element.5. The decoder of claim 1 , wherein the variable node processor comprises a format conversion circuit operable to convert the check node to variable node messages for a previous layer to a non-normalized format.6. The decoder of claim 1 , wherein the variable node processor comprises a first part and a second part claim 1 , the decoder further comprising a ...

MAGNETIC TAPE REWIND OVERWRITE DATA PROTECTION

A computer-implemented method for preventing overwriting of data, e.g., on a magnetic medium, includes receiving a write command to write to a magnetic tape. The current location of the magnetic tape is determined. A determination is also made as to whether data corresponding to the write command is at least one of: a size and type specified for a block at the current location. Execution of the write command is disallowed in response to determining that the data corresponding to the write command is not of the specified size and/or type. 1. A computer-implemented method , comprising:receiving a write command to write to a magnetic tape;determining a current location of the magnetic tape;determining whether data corresponding to the write command is at least one of: a size and type specified for a block at the current location; anddisallowing execution of the write command in response to determining that the data corresponding to the write command is not of the specified size and/or type.2. A computer-implemented method as recited in claim 1 , wherein the type of the data corresponds to a volume identifier.3. A computer-implemented method as recited in claim 1 , wherein the size specified for the block is different than a size specified for a user data block.4. A computer-implemented method as recited in claim 1 , wherein the block is a first block on the tape.5. A computer-implemented method as recited in claim 1 , wherein execution of the write command is disallowed in response to determining that the data corresponding to the write command is not of the specified size and type.6. A computer-implemented method as recited in claim 1 , wherein the method is performed in a tape drive.7. A computer-implemented method as recited in claim 6 , wherein the write command is received from a first host claim 6 , wherein the current location of the magnetic tape is at the block at a beginning of tape because of a rewind command received from a second host.8. A system claim 6 , ...

MAGNETIC HEAD, HEAD GIMBAL ASSEMBLY, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS

A magnetic head has a magnetic head slider that includes a recording element that generates a recording signal magnetic field, a microwave magnetic field generating element that generates a microwave magnetic field, a terminal electrode, and a first transmission line that interconnects the terminal electrode and the microwave magnetic field generating element. A second transmission line is connected to the terminal electrode, the second transmission line being used to transmit a microwave signal from the outside of the magnetic head slider to the magnetic head slider. A capacitor connected to the first transmission line is provided between the terminal electrode and the microwave magnetic field generating element. Accordingly, in the magnetic head, a microwave signal is efficiently propagated. 1. A magnetic head comprising a magnetic head slider that comprises a recording element that generates a recording signal magnetic field , a microwave magnetic field generating element that generates a microwave magnetic field , a terminal electrode , and a first transmission line that interconnects the terminal electrode and the microwave magnetic field generating element , wherein:a second transmission line is connected to the terminal electrode, the second transmission line being used to transmit a microwave signal from an outside of the magnetic head slider to the magnetic head slider; anda capacitor connected to the first transmission line is provided between the terminal electrode and the microwave magnetic field generating element.2. The magnetic head according to claim 1 , wherein each of the first transmission line and the second transmission line is a transmission line for use for a differential signal.3. The magnetic head according to claim 1 , wherein the capacitor is connected to the first transmission line in parallel to the microwave magnetic field generating element.4. The magnetic head according to claim 1 , wherein the first transmission line has an inductive ...

Magnetic recording and reproducing device and method of controlling magnetic recording and reproducing device

According to one embodiment, a magnetic recording and reproducing device which has a magnetic recording medium, a magnetic head, and a recording current output unit. Magnetic data is recorded on the magnetic recording medium. The magnetic head records the magnetic data on the magnetic recording medium. The recording current output unit supplies a recording current to the magnetic head so as to magnetize the magnetic head. A waveform of the recording current has a first slope for a first period to record data of first information continuously and a second slope for a following second period to switch the data to data of second information and to record the data of the second information. The first slope and the second slope are different from each other.

PSEUDO-DIFFERENTIAL MAGNETIC RECORDING SYSTEM AND METHOD INCORPORATING A DUMMY READ ELEMENT AND A DUMMY TRANSMISSION LINE

A system including a first transmission line, a second transmission line, a first element, a second element and a differential amplifier. The first element is configured to read a storage media to generate a read signal, where the first element is connected to the first transmission line. The second element is configured to detect interference and generate an interference signal, where the second element is connected to the second transmission line. The differential amplifier includes a first input and a second input, where the first input of the differential amplifier is connected to a the first transmission line and receives the read signal, and where the second input of the differential amplifier is connected to the second transmission line and receives the interference signal. 1. A system comprising:a first transmission line;a second transmission line;a first element configured to read a storage media to generate a read signal, wherein the first element is connected to the first transmission line;a second element configured to detect interference and generate an interference signal, wherein the second element is connected to the second transmission line; anda differential amplifier comprising a first input and a second input, wherein the first input of the differential amplifier is connected to a the first transmission line and receives the read signal, and wherein the second input of the differential amplifier is connected to the second transmission line and receives the interference signal.2. The system of claim 1 , wherein the second element is not configured to read data or information from a track.3. The system of claim 1 , comprising:a plurality of transmission lines comprising the first transmission line and not the second transmission line,wherein the read signal is a first read signal;a plurality of elements comprising the first element, wherein the plurality of elements are configured to read one or more tracks on the storage media to generate a ...

TWO-DIMENSIONAL MAGNETIC RECORDING SYSTEMS AND METHODS FOR MINIMIZING AND ACCOUNTING FOR INTER-MODULATION OF SIGNALS INDUCED IN ADJACENT READ ELEMENTS

A system including transmission lines, read elements, and differential amplifiers. The read elements are connected in series. Each of the read elements is connected to a respective pair of the transmission lines. The differential amplifiers are connected respectively to the read elements via the transmission lines. The differential amplifiers are configured to amplify differential signals received from the respective pairs of the transmission lines. 1. A system comprising:a plurality of transmission lines;a plurality of read elements connected in series, wherein each of the plurality of read elements is connected to a respective pair of the plurality of transmission lines; anda plurality of differential amplifiers connected respectively to the plurality of read elements via the plurality of transmission lines, wherein the plurality of differential amplifiers are configured to amplify differential signals received from the respective pairs of the plurality of transmission lines.2. The system of claim 1 , wherein a number of the plurality of transmission lines is twice a number of the plurality of read elements.3. The system of claim 1 , wherein a number of the plurality of read elements is equal to a number of the plurality of differential amplifiers.4. The system of claim 1 , wherein a number of the plurality of transmission lines is twice a number of the plurality of differential amplifiers.5. The system of claim 1 , wherein:the plurality of transmission lines comprises a first transmission line, a second transmission line, and a third transmission line;the plurality of read elements comprise a first element and a second element;the plurality of differential amplifiers comprise a first differential amplifier and a second differential amplifier;the first element is connected to the first transmission line;the second element is connected to the second transmission line and the third transmission line;the first transmission line is connected to a first input terminal ...

INDEPENDENTLY DRIVEN WRITE COILS

A writer assembly having two separately driven write coils allows a combined write field generated by the writer assembly to be fine turned and optimized for a particular application. Two preamplifiers may be incorporated into a printed circuit board in order to separately drive the write coils. In other implementations, there may be more than two write coils and corresponding preamplifiers. 1. A method comprising:independently driving at least two write coils within a writer assembly using separate preamplifiers.2. The method of claim 1 , wherein the separate preamplifiers drive the at least two write coils using one or more of different current magnitudes claim 1 , phases claim 1 , and polarities.3. The method of claim 1 , wherein the at least two write coils generate individual write fields that yield a combined write field.4. The method of claim 3 , wherein the combined write field is directed to a storage media via a write pole and a return pole to write data to the storage media.5. The method of claim 4 , wherein the at least two write coils are oriented on opposite sides of the write pole.6. The method of claim 1 , wherein each of the at least two write coils have one of a substantially planar orientation and a substantially helical orientation.7. The method of claim 1 , wherein at least one of the write coils utilizes at least three bond pads located on different turns of the write coil.8. A writer assembly comprising:a first write coil independently driven by a first preamplifier; anda second write coil independently driven by a second preamplifier.9. The writer assembly of claim 8 , wherein the first preamplifier drives the first write coil and the second preamplifier drives the second write coil using one or more of different current magnitudes claim 8 , phases claim 8 , and polarities.10. The writer assembly of claim 8 , wherein the first write coil and the second write coil generate individual write fields that yield a combined write field.11. The ...

MAGNETIC RECORDING AND REPRODUCING DEVICE

According to one embodiment, a magnetic recording and reproducing device includes a magnetic flux control layer provided between a main magnetic pole and an auxiliary magnetic pole, and a protective layer provided on an ABS of the auxiliary magnetic pole. The magnetic flux control layer includes an adjustment layer formed of a magnetic material includes one of Fe, Co or Ni and provided between a first conductive layer and a second conductive layer, and generates a spin torque and inverts a direction of magnetization in the adjustment layer, when current is supplied. A voltage Vb applied to the magnetic flux control layer is lower than a voltage Vba represented by an expression (1). 2. The magnetic recording and reproducing device of claim 1 , wherein the protective layer has a thickness of 1.0 to 2.5 nm.3. The magnetic recording and reproducing device of claim 1 , wherein the protective layer includes a surface layer formed of diamond-like carbon.4. The magnetic recording and reproducing device of claim 1 , wherein the voltage Vb applied to the magnetic flux control layer is 100 to 300 mV.5. The magnetic recording and reproducing device of claim 1 , wherein a temperature of the magnetic flux control layer in operation is 5 to 150° C.6. The magnetic recording and reproducing device of claim 1 , wherein an ambient atmosphere of the magnetic recording head has a humidity of 80% or less when the magnetic recording head operates.7. The magnetic recording and reproducing device of one of to claim 1 , wherein an ambient atmosphere of the magnetic recording head has an oxygen partial pressure of 20% or less when a pressure of whole air in the recording and reproducing device is 100%.8. The magnetic recording and reproducing device of claim 1 , further comprising a voltage controller connected to the magnetic recording head claim 1 , whereinthe voltage controller controls the voltage Vb applied to the magnetic flux control layer to be lower than the voltage Vba represented ...

MAGNETIC DISK DEVICE CONFIGURED TO SPECIFY A RANGE OF PREVIOUSLY WRITTEN TRACK THAT IS TO BE OVERLAPPED DURING A WRITE AND VERIFY DATA PREVIOUSLY WRITTEN IN THE SPECIFIED RANGE AFTER THE WRITE

A magnetic disk device includes a magnetic disk and a control circuit. The magnetic disk includes a first area where writing is performed in a manner such that a newly written track partially overlaps a previously written adjacent track. The control circuit is configured to specify a range of a second track, which is to be overlapped as a result of writing first data to a first track, write second data written in the specified range of the second track to a saving area prior to writing the first data to the first track, write the first data to the first track, and verify the second data in the second track after writing the first data to the first track. 1. A magnetic disk device comprising:a magnetic disk including a first area where writing is performed in a manner such that a newly written track partially overlaps a previously written adjacent track; anda control circuit configured to specify a range of a second track, which is to be overlapped as a result of writing first data to a first track, write second data written in the specified range of the second track to a saving area prior to writing the first data to the first track, write the first data to the first track, and verify the second data in the second track after writing the first data to the first track.2. The magnetic disk device according to claim 1 , whereinthe magnetic disk further includes a second area different from the first area, andthe control circuit transfers the second data written to the saving area to the second area when the verification of the second data fails.3. The magnetic disk device according to claim 1 , wherein the first data has a size equal to or less than a size of the saving area.4. The magnetic disk device according to claim 1 , further comprising a volatile memory claim 1 ,wherein the control circuit uses the volatile memory as the saving area.5. The magnetic disk device according to claim 4 , wherein the control circuit is configured to protect contents of the saving ...

MAGNETIC DISK DEVICE AND METHOD FOR OPTIMIZING RECORDING CURRENT

A magnetic disk device includes a magnetic disk that includes a plurality of zones divided in a radial direction, a plurality of tracks in each of the zones, and a plurality of sectors in each of the tracks divided in a circumferential direction, a magnetic head configured to read and write data to and from the magnetic disk, and a control unit configured to determine a setting value of a recording current to be applied to the magnetic head when writing to each of a plurality of sections of a first sector, based on error rates in data read from a second sector that is in the same zone as the first sector and to which a write was performed while changing setting values of recording currents applied to the magnetic head while writing to each of a plurality of sections of the second sector. 1. A magnetic disk device , comprising:a magnetic disk that includes a plurality of zones divided in a radial direction, a plurality of tracks in each of the zones, and a plurality of sectors in each of the tracks divided in a circumferential direction;a magnetic head configured to read and write data to and from the magnetic disk; anda control unit configured to determine a setting value of a recording current to be applied to the magnetic head when writing to each of a plurality of sections of a first sector, based on error rates in data read from a second sector that is in the same zone as the first sector and to which a write was performed while changing setting values of recording currents applied to the magnetic head while writing to each of a plurality of sections of the second sector.2. The magnetic disk device according to claim 1 , further comprising:a temperature sensor configured to measure an internal temperature of the magnetic disk device, whereinthe control unit determines the setting value of the recording current to be applied to the magnetic head when writing to each of the plurality of sections of the first sector upon determining that the measured internal ...

Magnetic Head With Integrated Write Driver

An apparatus and associated method generally relate to data writing and more specifically to writing data to a rotating media. An embodiment of such an apparatus comprises a slider body, a transducer and a write driver. The transducer comprises a writer. The write driver is integrated on the slider body, and directly connected to the writer. 1. An apparatus comprising a data transducer attached to a slider body on an air bearing surface (ABS) , the data transducer connected to a write driver mounted on the slider body , the write driver separated from the ABS , slider body , and a flexure.2. The apparatus of claim 1 , wherein a bottom surface of the slider body corresponds with the ABS claim 1 , the write driver attached to and separated from a top surface of the slider body claim 1 , the top surface opposite the bottom surface.3. The apparatus of claim 1 , wherein the data transducer and slider body are each positioned on the ABS.4. The apparatus of claim 1 , wherein first and second bond pads contact the slider body and a driver substrate claim 1 , the driver substrate separated from the slider body and in contact with the write driver.5. The apparatus of claim 1 , wherein the data transducer comprises a data writer element and a data reader element.6. The apparatus of claim 1 , wherein the write driver has first and second separate bond pads each positioned on one or more external surfaces of the write driver claim 1 , the first bond pad electrically connected to the flexure claim 1 , the second bond pad electrically connected to the data transducer.7. The apparatus of claim 1 , wherein a write data input provides a data signal to the write driver.8. An apparatus comprising a data transducer attached to a slider body on an air bearing surface (ABS) claim 1 , the data transducer connected to a write driver mounted on the slider body claim 1 , the write driver separated from the ABS claim 1 , a flexure claim 1 , and a slider mount claim 1 , at least one bond pad ...

READ-WRITE NON-ERASABLE MEMORY WITH LASER RECORDING AND METHOD OF RECORDING

A nonvolatile memory comprising at least one ferromagnetic region having permeability which changes from a first state to a second state of lower permeability upon heating; at least one laser operatively associated with the at least one ferromagnetic region which selectively provides heat to the ferromagnetic region to change its p permeability; and a plurality of connectors operatively connected to the at least one laser and adapted to be connected to a current source that provides a current which causes the laser to change the at least one ferromagnetic region from a first state to a second state. Optionally, the memory is arranged as an array of memory cells. Optionally, each cell has a magnetic field sensor operatively associated therewith. Optionally, the nonvolatile memory is radiation hard. Also, a method of recording data by heating at least one ferromagnetic region to change its permeability. 1. A memory system for storing information comprising:a substrate;magnetic material operatively associated with the substrate, the magnetic material having at least one ferromagnetic region configured to store data having a first state of high permeability and a second state of low permeability; the at least one ferromagnetic region in the first state configured to be modifiable to a state of low permeability upon heating to permit modification of the bits of data;at least one laser operatively associated with the at least ferromagnetic region which selectively provides heat to the at least one ferromagnetic region to change its permeability; anda plurality of connectors operatively connected to the laser and adapted to be connected to a current source that provides a current which causes the laser to emit light that heats to change the permeability of the at least one ferromagnetic region.2. The memory system of further comprising at least one magnet configured to provide at least one magnetic probe field; the ferromagnetic regions being subjected to the at least one ...

CHANGING CHARACTERISTICS OF SIGNAL PATTERNS TO REDUCE ADJACENT TRACK INTERFERENCE

First and second signal patterns are used to write corresponding portions of first and second adjacent tracks to a magnetic storage medium. A characteristic of the first signal pattern is changed based on the second signal pattern, the changing of the characteristic reducing an adjacent track interference affecting the second track. 1. A method comprising:determining first and second signal patterns used to write corresponding portions of first and second adjacent tracks to a storage medium, the first and second signal patterns resulting in an alignment of short and long transitions between the first and second adjacent tracks; andchanging a preamplifier boost used to write the short transitions to reduce an adjacent track interference caused by the alignment of the long and short transitions when writing the first and second tracks.2. The method of claim 1 , wherein the first track is written before the second track claim 1 , and wherein the determining of the second signal pattern comprises buffering the second signal pattern before writing the second track.3. The method of claim 1 , wherein the second track is written before the first track.4. The method of claim 1 , wherein the second signal pattern comprises a read-ahead signal of the second track obtained via a reader from the storage medium.5. The method of claim 1 , wherein the first track and second tracks are bit-level aligned.6. The method of claim 1 , wherein changing of the preamplifier boost comprises changing one or more of an overshoot of a signal used to write the short transitions claim 1 , an asymmetry of the signal claim 1 , and a rise time of the signal.7. The method of claim 1 , wherein the first and second adjacent tracks are shingled tracks.8. The method of claim 1 , wherein the first and second tracks are read together via a multiple sensor magnetic reader.9. The method of claim 1 , wherein the first and second tracks are read together via a two-dimensional recording channel.10. The method ...

METHOD AND SYSTEM FOR PRESERVING DATA OF A STORAGE DEVICE

A method and system for preserving data of a storage device are disclosed. In one embodiment, the method includes determining a number of times data is written to a first track in a first region of a storage medium, and rewriting data from a second track that is adjacent to the first track in the first region if the number of times data is written to the first track in the first region exceeds a first predetermined threshold. The method further includes determining a number of times data is rewritten to the second track in the first region, and relocating data from the second track in the first region to a second region of the storage medium if the number of times data is rewritten to the second track in the first region exceeds a second predetermined threshold. 1. A method comprising:determining a number of times data is written to a first track in a first region of a storage medium;rewriting data from a second track that is adjacent to the first track in the first region if the number of times data is written to the first track in the first region exceeds a first predetermined threshold;determining a number of times data is rewritten to the second track in the first region; andrelocating data from the second track in the first region to a second region of the storage medium if the number of times data is rewritten to the second track in the first region exceeds a second predetermined threshold.2. The method of claim 1 , further comprising rewriting data from a third track that is adjacent to the first track in the first region if the number of times data is written to the first track in the first region exceeds a third predetermined threshold claim 1 , and the first track is positioned between the second track and the third track.3. The method of claim 2 , further comprising relocating data from the third track in the first region to the second region of the storage medium if a number of times data is rewritten to the third track in the first region exceeds a ...

Multiprocessor Computing Apparatus with Wireless Interconnect and Non-Volatile Random Access Memory

A fan less Multiprocessor Computing Apparatus (MCA) is housed in a metallic Enclosure (ME) that acts as a heat sink and provides extended surface area for heat dissipation. The ME also acts as an electro-magnetic-Shield that provides immunity from Electro-Magnetic-Interference (EMI) from external stray magnetic fields to wireless communications among components of MCA. The Wireless Interconnect (WLI) involving Transceiver Antenna can use whole range of radio, microwave, and optical frequencies involving transceivers and antennas. Printed Circuit Boards of MCA are mounted on inside of metallic surfaces of ME of any required size and shape. MEs are filled with vacuum or clean dust free air without any suspended particles for efficient and reliable communications. Electro-magnetically shielded and sealed MEs housing MCAs are made dust and water proof so that they can be placed under water in a sea or a river, particularly MCAs constituting large data/cloud centres. Also, Shared Memory Units are made up of non-volatile static Magneto-Optical or Optical recordable, erasable, and recordable media in square/rectangular form factor.

MOTOR AND DISK DRIVE

A motor for a disk drive includes a stationary unit, a bearing mechanism attached to the stationary unit, and a rotation unit supported on the stationary unit rotatably around a central axis via the bearing mechanism. The stationary unit includes a base portion that is a part of a housing defining an internal space sealed in the disk drive and includes a recess portion recessed from a side of the internal space toward an outside of the housing and not penetrated. The bearing mechanism includes a shaft extending in a direction of the central axis and a sleeve surrounding at least a portion of an outer circumferential surface of the shaft. A lower end portion of the shaft is press-fit and glued into the recess portion, and a lower surface of the base portion including a base step portion extending toward an axially upper side. 1. A motor for a disk drive , the motor comprising:a stationary unit;a bearing mechanism attached to the stationary unit; anda rotation unit supported on the stationary unit rotatably around a central axis via the bearing mechanism; whereinthe stationary unit includes a base portion;the base portion is a portion of a housing defining an internal space sealed in the disk drive and includes a recess portion that is recessed from a side of the internal space toward an outside of the housing and that is not penetrated;the bearing mechanism includes a shaft extending in a direction of the central axis and a sleeve surrounding at least a portion of an outer circumferential surface of the shaft;the shaft has a cylindrical shape including a hollow portion extending along the central axis;an inner circumferential surface of the shaft includes a shaft step portion that extends directly radially outward from the central axis, the shaft step portion being provided at an axially upper end of the hollow portion;a fixed step portion is provided at an axially lower side of the shaft step portion, the fixed step portion extending directly radially outward from ...

Efficient connection management in a sas target

A method includes pre-configuring a hardware-implemented front-end of a storage device with multiple contexts of respective connections conducted between one or more hosts and the storage device. Storage commands, which are received in the storage device and are associated with the connections having the pre-configured contexts, are executed in a memory of the storage device using the hardware-implemented front-end. Upon identifying a storage command associated with a context that is not pre-configured in the hardware-implemented front-end, software of the storage device is triggered to configure the context in the hardware-implemented front-end, and the storage command is then executed using the hardware-implemented front-end in accordance with the context configured by the software.

SELF-CONTROLLED LASER PULSING FOR THERMALLY ASSISTED RECORDING

A method of storing data includes providing a write signal for a write head of a hard disk drive, generating a transition pulse signal derived from the write signal using a transition pulse generator, and generating a logic signal to drive a thermal source associated with the write head of the hard disk drive. The logic signal includes the logical summation of a cyclical base pulse signal and the transition pulse signal. 1. A method of storing data , the method comprising:providing a write signal for a write head of a hard disk drive;generating a transition pulse signal derived from the write signal using a transition pulse generator;configuring a pulse shaping register to store the characteristics of a cyclical base pulse signal, comprising the frequency, pulse width and pulse interval; andgenerating a logic signal to drive a thermal source associated with the write head of the hard disk drive, the logic signal comprising the logical summation of the cyclical base pulse signal and the transition pulse signal; wherein the characteristics of the base pulse signal are controlled by the pulse shaping register.2. The method of claim 1 , wherein the write signal is provided to a preamplifier of the hard disk drive system and wherein the preamplifier of the hard disk drive system includes the transition pulse generator; and wherein a preamplifier of the hard disk drive includes a base pulse generator claim 1 , configured to generate a base pulse signal in the absence of an external pulse signal and in accordance with a pulse shaping register.3. The method of claim 1 , further comprising generating the base pulse signal with a base pulse generator.4. The method of claim 3 , wherein a preamplifier of a hard drive system includes the base pulse generator.5. The method of claim 3 , wherein generating the base pulse signal includes generating the base pulse signal in the absence of an external pulse signal.6. (canceled)7. (canceled)8. The method of claim 1 , further comprising ...

MEASUREMENT CIRCUIT FOR MICROWAVE ASSISTED MAGNETIC RECORDING

According to one embodiment, a disk device includes a disk includes a recording layer, a recording head includes a main pole configured to apply a recording magnetic field onto the recording layer, and a microwave oscillator adjacent to the main pole, configured to apply a microwave magnetic field to the recording layer, a current supply circuit configured to supply a current to the microwave oscillator, and a switching circuit configured to switch a direction of current flow to the microwave oscillator. 1. A disk device comprising:a disk comprising a recording layer;a recording head comprising a main pole configured to apply a recording magnetic field onto the recording layer, and a microwave oscillator adjacent to the main pole, configured to apply a microwave magnetic field to the recording layer;a current supply circuit configured to supply a current to the microwave oscillator;a switching circuit configured to switch a direction of current flow to the microwave oscillator; anda measurement circuit configured to measure first oscillation characteristics of the microwave oscillator when a current is supplied to the microwave oscillator in a first direction of current flow, to measure second oscillation characteristics of the microwave oscillator when a current is supplied to the microwave oscillator in a second direction of current flow, and to compare the measured first and second oscillation characteristics, andwherein the switching circuit is configured to select and switch to the first direction of current flow or the second direction of current flow, with which better oscillation characteristics of the microwave oscillator can be obtained.2. The disk device of claim 1 , whereinthe microwave oscillator comprises a first oscillatory layer, and a second oscillatory layer stacked on the first oscillatory layer via an intermediate layer.3. The disk device of claim 2 , whereinthe recording head comprises an air bearing surface opposing the recording layer, and the ...

ELECTROSTATIC DISCHARGE PROTECTION FOR A MAGNETORESISTIVE SENSOR

A magneto-resistive (MR) sensor protection circuit is disclosed, for the protection of an MR sensor. The MR sensor may have a safe operating voltage range, a normal operating voltage range within the safe operating voltage range, and two terminals coupled to a read channel circuit, including a positive terminal and a negative terminal. The MR sensor protection circuit may have positive and negative protection threshold voltage ranges. The MR sensor protection circuit may also have a plurality of N-channel field-effect transistors (NFETs) that are coupled to the positive terminal and to the negative terminal, and configured to, in response to a voltage between the two terminals being within either the positive or the negative protection threshold voltage range, limit the voltage between the terminals by shunting current between the positive terminal and the negative terminal. 1. A data storage device comprising:a magnetic recording medium configured to contain stored data;an MR sensor having a safe operating voltage range, a normal operating voltage range within the safe operating voltage range, and two terminals coupled to a read channel circuit, including a positive terminal and a negative terminal, the MR sensor configured to read the stored data from the magnetic recording medium; and a positive protection threshold voltage range outside of and above the normal operating voltage range and within the safe operating voltage range;', 'a negative protection threshold voltage range outside of and below the normal operating voltage range and within the safe operating voltage range;', 'a first N-channel field-effect transistor (NFET) that is coupled to the positive terminal and to the negative terminal, and configured to, in response to a voltage between the two terminals being within the positive protection threshold voltage range, limit the voltage between the terminals by shunting current between the positive terminal and the negative terminal, and;', 'a second NFET ...

HEAT ASSISTED MAGNETIC RECORDING FOR BIT-PATTERNED MEDIA

A heat-assisted magnetic recording (HAMR) device includes a controller that selects a power for operating a heat source for a data write to a target data track. According to one implementation, the controller selects the power based on an assessment of whether the target data track is bounded by any data-storing tracks. A first power is selected when the data track is not bounded by any data-storing tracks and a second lower power is selected when the data track is bounded by one or more data-storing tracks. In another implementation, the controller writes to different partitioned regions of a storage media with different powers of the heat source. The controller selects a storage location for data based on an expected write error rate and environmental conditions within the HAMR device. 1. A storage device comprising:a heat-assisted magnetic recording (HAMR) head including a heat source; anda controller that selects a power for the heat source to write data to a target data track based on a whether the target data track is bounded by any data-storing tracks.2. The storage device of claim 1 , wherein the controller selects a first power if the target data track is not bounded by any data-storing tracks and selects a second power lower than the first power if the target data track is bounded by at least one data-storing track.3. The storage device of claim 2 , wherein the controller relaxes a positioning requirement of the HAMR head when writing data while operating the heat source at the first power and tightens the positioning requirement of the HAMR head while operating the heat source at the second power.4. The storage device of claim 2 , wherein the controller is configured to write data to a series of alternating data tracks at the first power until a capacity condition is satisfied.5. The storage device of claim 1 , wherein the storage media is a bit patterned media (BPM).6. One or more tangible computer-readable storage media encoding computer-executable ...

SWITCHING PERIOD CONTROL OF MICROWAVE ASSISTED MAGNETIC RECORDING FOR POLE ERASURE SUPPRESSION

A magnetic recording system for preventing data loss resulting magnetic oscillator current. The magnetic recording system includes a magnetic write head with a magnetic write pole, a magnetic oscillator near the magnetic write pole, and a write coil for magnetizing the write pole. Circuitry is connected with the magnetic write coil to supply a current to the write coil and connected with the magnetic oscillator to supply a current to the magnetic oscillator. The circuitry is configured to ensure that the current to the magnetic oscillator does not inadvertently magnetize the write pole after the magnetic write pole has demagnetized. 1. A magnetic recording system , comprising:a magnetic write pole;a write coil configured to magnetize the magnetic write pole;a magnetic oscillator formed adjacent to the magnetic write pole, the magnetic oscillator begin configured to cause an oscillating magnetic field; andcircuitry connected to the write coil and the magnetic oscillator, the circuitry being configured to ensure that current flow through the write coil terminates before the write pole has completely demagnetized upon termination of writing.2. The magnetic recording system as wherein the circuitry is configured to shorten a time in which current flow through the magnetic oscillator stops upon shut down of the magnetic oscillator.3. The magnetic recording system as in claim 1 , wherein the circuitry is configured to terminate current to the magnetic oscillator prior to terminating current to the write coil.4. The magnetic recording system as in claim 1 , wherein the circuitry is configured to extend the time to demagnetize the write pole to ensure that electrical current flow through the magnetic oscillator has terminated before the write pole has demagnetized.5. The magnetic recording system as in claim 1 , wherein the magnetic oscillator is a spin torque oscillator.6. A magnetic recording system claim 1 , comprising:a magnetic write pole;a write coil configured to ...

CONFIGURABLE WRITE CURRENT OVERSHOOT SYSTEM FOR HDD WRITE DRIVER

A hard disk drive write drive method and integrated circuit that provide a configurable overshoot current based on the length of the pattern in the write current signal that is being written to the hard disk by the write driver. The hard disk write driver adds a first overshoot current to all patterns in the write current signal and adds an additional second overshoot current to patterns in the write current signal shorter than a first duration. The hard disk drive write driver utilizes an H-bridge circuit configured to add the first overshoot current and the additional second overshoot current to the write current signal. The H-bridge circuit is comprised of four switching elements that are configured to generate a first overshoot current for all pattern transitions of the write current signal and generate a second overshoot current for pattern transitions shorter than the first duration. 1. A process of forming a write current signal used in a hard disk drive comprising:(a) receiving a write data input signal having data pulses, each data pulse having a start transition, an end transition, and a time T in length between transitions, and the time T between transitions of different pulses are integral numbers of time T in length;(b) generating a write current signal of write pulses having start transitions in accordance with the data pulses of the write data input signal;(c) determining the lengths T of the data pulses;(d) for data pulses having a length T greater than 1T, producing a first overshoot current at the start transition of a write pulse for a first time duration and a first current value; and(e) for data pulses having a length of 1T, producing a second overshoot current at the start transition of a write pulse for a second time duration and a second current value.2. The process of in which the first time duration and the second time duration are the same.3. The process of in which the first current value is Ios and the second current value is Ios+IosADD. ...

IMPEDANCE MATCHING FOR AN INTEGRATED CIRCUIT OF A MAGNETIC DISK DEVICE

An integrated circuit connectable to a signal transmission path of a storage device includes an impedance setting circuit including a plurality of switches, a detector configured to detect an input signal level, and a decoder. The decoder controls one or more switches of the impedance setting circuit based on the detected input signal level so as to match an impedance of the integrated circuit with an impedance of the signal transmission path. 1. An integrated circuit connectable to a signal transmission path of a storage device , comprising:an impedance setting circuit including a plurality of switches;a detector configured to detect an input signal level; anda decoder configured to control one or more of the switches of the impedance setting circuit based on the detected input signal level so as to match an impedance of the integrated circuit with an impedance of the signal transmission path.2. The integrated circuit according to claim 1 , wherein the detector is connected to a terminal and the input signal level is at a first level when the terminal is connected to a power line and at a second level when the terminal is connected to a ground line.3. The integrated circuit according to claim 1 , whereinthe signal transmission path includes an output signal transmission path and an input signal transmission path, andthe impedance setting circuit includes a first impedance setting circuit for the output signal transmission path and a second impedance setting circuit for the input signal transmission path.4. The integrated circuit according to claim 3 , whereineach of the first and second impedance setting circuits includes a first resistor and a second resistor having a higher resistance than the first resistor.5. The integrated circuit according to claim 4 , wherein the second resistor has twice the resistance of the first resistor.6. The integrated circuit according to claim 1 , wherein the storage device includes a magnetic recording disk claim 1 , and a read ...

Systems and Methods for Multi-Path Preamplifier Fault Processing

Systems and method relating generally to data processing, and more particularly to systems and methods for utilizing multiple data streams for data recovery from a storage device. 1. A preamplifier circuit , the circuit comprising: a first flaw scan detector circuit operable identify a first flaw on a first surface of a storage medium based upon a first information set corresponding to the first surface; and', 'a second flaw scan detector circuit operable identify a second flaw on a second surface of a storage medium based upon a second information set corresponding to the first surface., 'a single integrated circuit including2. The preamplifier circuit of claim 1 , wherein the single integrated circuit further includes:an amplifier circuit operable to amplify a third information set derived from a third sensor.3. The preamplifier circuit of claim 2 , wherein:the information corresponding to the first surface is derived from a first sensor disposed in relation to the first surface; andthe information corresponding to the second surface is derived from a second sensor disposed in relation to the second surface.4. The preamplifier circuit of claim 3 , wherein the preamplifier circuit is implemented as part of a storage system claim 3 , and wherein the storage system includes:a head disposed in relation to the first surface of the storage medium, wherein the head includes the first sensor and the third sensor.5. The preamplifier circuit of claim 4 , wherein the first sensor is a temperature sensor claim 4 , and the third sensor is a data sensor.6. The preamplifier circuit of claim 4 , wherein the storage system further includes:the storage medium.7. The preamplifier circuit of claim 6 , wherein the storage system is a hard disk drive.8. The preamplifier circuit of claim 1 , wherein the first flaw scan detector is a first thermal asperity based flaw scan detector circuit claim 1 , and wherein the second flaw scan detector is a second thermal asperity based flaw scan ...

MAGNETIC RECORDING HEAD, MAGNETIC HEAD ASSEMBLY, MAGNETIC RECORDING APPARATUS, AND MAGNETIC RECORDING METHOD

An example magnetic recording apparatus includes a magnetic recording medium, a magnetic recording head and a signal processor. The magnetic recording head includes a first magnetic pole; a second magnetic pole; a spin torque oscillator; a first coil to magnetize the first magnetic pole; and a second coil through which a current is passed independently of the first coil. The signal processor writes and reads a signal on the magnetic recording medium by using the magnetic recording head and includes a first current circuit to supply a recording current to the first coil and a second current circuit to supply a modulating current to the second coil. 1. A magnetic recording apparatus , comprising:a magnetic recording medium; a first magnetic pole to apply a recording magnetic field to the magnetic recording medium;', 'a second magnetic pole provided parallel to the first magnetic pole;', 'a spin torque oscillator at least a portion of which is provided between the first magnetic pole and the second magnetic pole;', 'a first coil to magnetize the first magnetic pole; and', 'a second coil through which a current is passed independently of the first coil; and, 'a magnetic recording head including a first current circuit to supply a recording current to the first coil, the recording current including a recording signal to be recorded on the magnetic recording medium; and', 'a second current circuit to supply a modulating current to the second coil, wherein, 'a signal processor to write and read a signal on the magnetic recording medium by using the magnetic recording head, the signal processor includingthe modulating current includes either one of a signal changing at a frequency higher than that of the recording signal and a signal having the same frequency as the recording signal and changing an absolute value thereof in one cycle.2. The apparatus according to claim 1 , whereinthe second current circuit includes a modulation signal current circuit and a controlling ...

STORAGE DEVICE HAVING DEGAUSS CIRCUITRY CONFIGURED FOR GENERATING DEGAUSS SIGNAL WITH ASYMMETRIC DECAY ENVELOPES

A hard disk drive or other storage device comprises a storage medium, a write head configured to write data to the storage medium, and control circuitry coupled to the write head. The control circuitry comprises degauss circuitry coupled to or otherwise associated with one or more write drivers. The degauss circuitry is configured to generate an asymmetric degauss signal to be applied to the write head. The asymmetric degauss signal has a waveform with upper and lower decay envelopes that are asymmetric about a specified degauss current level, such as a substantially zero current level. 1. An apparatus comprising:control circuitry adapted for coupling to a write head configured to write data to a storage medium;wherein the control circuitry comprises:a write driver; anddegauss circuitry associated with the write driver and configured to generate an asymmetric degauss signal to be applied to the write head, the asymmetric degauss signal having a waveform with upper and lower decay envelopes having respective different decay rates.2. The apparatus of wherein the upper and lower decay envelopes of the asymmetric degauss signal waveform comprise respective positive side and negative side decay envelopes.3. The apparatus of wherein the upper and lower decay envelopes are asymmetric about a substantially zero current level.4. The apparatus of wherein the degauss circuitry comprises:a first signal generator configured to generate a symmetric degauss signal having a waveform with upper and lower decay envelopes that are symmetric about a specified degauss current level;a second signal generator configured to generate a bias signal; anda signal combiner having first and second inputs coupled to respective outputs of the first and second signal generators and configured to combine the symmetric degauss signal and the bias signal to form the asymmetric degauss signal.5. The apparatus of wherein the degauss circuitry further comprises:a detector configured to detect a polarity ...

METHOD AND ELECTRONIC DEVICE FOR SECURE MAGNETIC PULSE TRANSMISSION

An electronic device and related operations are disclosed, including a communication circuit, a memory and a magnetic stripe transmission (MST) module for radiating a magnetic pulse. A processor implements the operations, including: controlling the MST module to change an emitted radiation pattern of the magnetic pulse in prespecified order to iteratively emit the plurality of radiation patterns, in response to detecting a prespecified event, selecting a presently emitted radiation pattern of the magnetic pulse, and storing information corresponding to the selected radiation pattern in the memory, or transmitting the information corresponding to the selected radiation pattern to the server. 1. An electronic device comprising:a communication circuit configured to communicate with a server;a memory configured to store secure data and a plurality of radiation patterns;a magnetic stripe transmission (MST) module configured to radiate a magnetic pulse communicating the secure data; anda processor electrically connected with the memory, the communication circuit, and the MST module, wherein the processor is configured to:control the MST module to change an emitted radiation pattern of the magnetic pulse in prespecified order to iteratively emit the plurality of radiation patterns;in response to detecting a prespecified event, select a presently emitted radiation pattern of the magnetic pulse; andstore information corresponding to the selected radiation pattern in the memory, or transmit the information corresponding to the selected radiation pattern to the server.2. The electronic device of claim 1 , wherein the processor is configured to:update the information related to the selected radiation pattern when the prespecified event is redetected.3. The electronic device of claim 1 , wherein storing the information and transmitting the information are both executed responsive to detecting successful completion of a transaction corresponding to the secure data.4. The ...

SKEW-AWARE DISK FORMAT FOR ARRAY READER BASED MAGNETIC RECORDING

A method of reading data in a multi-reader two-dimensional magnetic recording system includes determining a position of a multi-reader head, selecting a mode for reading the data of a magnetic recording medium as a function of the position of the multi-reader head, and reading the data of the magnetic recording medium in the selected mode. 1. A method of reading data in a multi-reader two-dimensional magnetic recording system , the method comprising:determining a position of a multi-reader head;selecting a mode for reading the data of a magnetic recording medium as a function of the position of the multi-reader head; andreading the data of the magnetic recording medium in the selected mode.2. The method of claim 1 , wherein the position is determined relative to a diameter of the magnetic recording medium.3. The method of claim 2 , the method further comprising determining a cross-track spacing between readers of the multi-reader head that corresponds to the position of the multi-reader head claim 2 , the step of selecting the mode further comprising reading a zone table to determine the mode corresponding to the cross-track spacing.4. The method of claim 1 , wherein the position is determined relative to a track of the magnetic recording medium.5. The method of claim 1 , further comprising providing a zone table comprising indications of a plurality of modes claim 1 , each mode corresponding to a different position of the multi-reader head.6. The method of claim 5 , wherein the step of selecting the mode further comprises reading the zone table to determine the mode corresponding to the position of the multi-reader head.7. The method of claim 1 , wherein the mode is a multiple input single output mode.8. The method of claim 7 , further comprising inputting the data read by one or more readers of the multi-reader head into one joint equalizer.9. The method of claim 1 , wherein the mode is a multiple input multiple output mode.10. The method of claim 9 , further ...

MAGNETIC RECORDING AND REPRODUCING APPARATUS

A magnetic recording and reproducing apparatus includes a magnetic recording medium including a recording layer in which at least two magnetic layers are layered on a non-magnetic substrate; and a magnetic head including a main magnetic pole for applying a recording magnetic field in a direction substantially perpendicular to a recording face of the magnetic recording medium and a microwave generating element that generates a microwave magnetic field. The relationship between a thickness Ts of a magnetic layer having a lowest magnetic anisotropy energy among the at least two magnetic layers composing the recording layer of the magnetic recording medium, and a thickness Tt of the recording layer is Ts/Tt≦0.2. The microwave generating element applies the microwave magnetic field having a width broader than the width of the recording magnetic field generated by the main magnetic pole of the magnetic head to the magnetic recording medium.

MICROWAVE-ASSISTED MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING APPARATUS INCLUDING THE SAME

A microwave-assisted magnetic recording head according to an embodiment includes: a magnetic pole; a magnetic shield including a first portion and a second portion connecting to the first portion, a gap being present between the first portion and the magnetic pole; a recording coil disposed to at least one of the magnetic pole and the magnetic shield; and a spin torque oscillator including a nonmagnetic intermediate layer extending within and outside the gap, an oscillation layer disposed on a portion of the nonmagnetic intermediate layer in the gap, and a spin injection layer in which a magnetization direction is pinned and which is disposed on a portion of the nonmagnetic intermediate layer outside the gap so as to be separated from the oscillation layer. 1. A microwave-assisted magnetic recording head comprising:a magnetic pole;a magnetic shield including a first portion and a second portion connecting to the first portion, a gap being present between the first portion and the magnetic pole;a recording coil disposed to at least one of the magnetic pole and the magnetic shield; anda spin torque oscillator including a nonmagnetic intermediate layer extending within and outside the gap, an oscillation layer disposed on a portion of the nonmagnetic intermediate layer in the gap, and a spin injection layer in which a magnetization direction is pinned and which is disposed on a portion of the nonmagnetic intermediate layer outside the gap so as to be separated from the oscillation layer.2. The recording head according to claim 1 , wherein the first portion and the second portion form a magnetic path with the magnetic pole claim 1 , and the gap serves as a recording gap disconnecting the magnetic path.3. The recording head according to claim 1 , wherein the spin injection layer injects spins to the oscillation layer via the nonmagnetic intermediate layer.4. The recording head according to claim 1 , wherein the spin injection layer includes a first spin injection portion ...

ESD Protection Surface Charge Control Recording Head

Electrostatic discharge protection can be afforded to a data recording head in accordance with various embodiments. A data recording head may consist of a circuit having a preamp ground connected to a ground substrate via a ground trace. The ground trace can consist of a first leg connected to the ground substrate and a second leg with an open connection extending from a dice line. 1. An apparatus comprising a circuit comprising a preamp ground connected to a ground substrate via a ground trace , the ground trace comprising a first leg connected to the ground substrate and a second leg with an open connection extending from a dice line.2. The apparatus of claim 1 , wherein the first leg has a greater resistance than the second leg.3. The apparatus of claim 1 , wherein the ground substrate comprises AlTiC.4. The apparatus of claim 1 , wherein the preamp ground is concurrently connected to the ground substrate claim 1 , a data reader claim 1 , and a data writer.5. The apparatus of claim 1 , wherein the second leg is positioned between a resistor of the first leg and the preamp ground.6. The apparatus of claim 5 , wherein the open connection comprises a conductive trace ending at an insulating location.7. The apparatus of claim 1 , wherein the ground substrate is positioned on an air bearings surface (ABS).8. The apparatus of claim 1 , wherein the circuit is positioned on a transducing head of a data storage system.9. The apparatus of claim 1 , wherein the circuit is positioned wholly on a single wafer.10. A system comprising a controller connected to a surface charge control circuit comprising a preamp ground connected to a ground substrate via a ground trace claim 1 , the first ground trace comprising a first leg connected to the ground substrate and a second leg with an open connection extending from a dice line and terminating at an insulated location.11. The system of claim 10 , wherein the preamp ground is concurrently connected to a reader heater and a writer ...

Magnetic Recording System With Ternary Pattern Dependent Write Signaling

A storage system includes a magnetic write head, a magnetic storage medium, a write data circuit having a write data output and a magnet length signal output, and a preamplifier that receives the write data and a magnet length signal from the write data circuit, and sets at least one write current characteristic through the magnetic write head based at least in part on the magnet length signal. The write data circuit processes write data to be recorded on the magnetic storage medium by the magnetic write head. The magnet length signal output communicates magnet lengths in the write data. 1. A storage system , comprising:a magnetic write head;a magnetic storage medium;a write data circuit comprising a write data output to output write data and a magnet length signal output to output a magnet length signal that communicates magnet lengths in the write data, wherein the write data circuit is operable to process the write data to be recorded on the magnetic storage medium by the magnetic write head, and wherein at least some states of the magnet length signal are mapped to the magnet lengths to communicate the magnet lengths; anda preamplifier operable to receive the write data and the magnet length signal from the write data circuit, and to set at least one write current characteristic through the magnetic write head based at least in part on the magnet length signal.2. The storage system of claim 1 , wherein the write data circuit comprises a pattern detector operable to detect the magnet lengths in the write data.3. The storage system of claim 1 , wherein the preamplifier comprises a pattern dependent write controller operable to sample the magnet length signal to retrieve the magnet lengths.4. The storage system of claim 3 , wherein the pattern dependent write controller comprises a sampling clock enable signal operable to preclude the pattern dependent write controller from sampling the magnet length signal at transitions of the write data identified by previous ...

RECORDING APPARATUS AND RECORDING APPARATUS CONTROL METHOD

A recording apparatus includes a head unit, which includes a driver, and a recording data transmitter that transfers recording data to the head unit via a signal line. The recording apparatus further includes a switching unit in the head unit that switches a driving signal applied to the driver between conductive and nonconductive states based on the transferred recording data, a partition signal output unit in the recording data transmitter that outputs a partition signal that partitions a data signal of the recording data to the head unit in response to switching by the switching unit, and a data selector in the head unit that selects data to be discarded from the transferred recording data based on the partition signal. 1. A recording apparatus , comprising:a head unit including a driver to drive a recording head;a recording head controller to output a drive signal to the driver to control operation of the head unit;a recording data transmitter provided in the recording head controller to transfer recording data to the head unit via a signal line;a switching unit provided in the head unit to switch the driving signal applied to the driver between conductive and nonconductive states based on the transferred recording data;a partition signal output unit provided in the recording data transmitter to output a partition signal that partitions a data signal of the recording data to the head unit, in response to switching by the switching unit; anda data selector provided in the head unit to select data to be discarded from the transferred recording data based on the partition signal.2. The recording apparatus according to claim 1 , wherein:the partition signal output unit outputs an invalid data identification signal that partitions the data signal into a valid period in which the recording data is transferred and an invalid period in which the recording data is not transferred; andthe data selector discards data based on the data signal corresponding to the invalid ...

THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING

A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current. 1. An apparatus , comprising:a laser diode configured to facilitate heat assisted magnetic recording in a lasing state;a sensor, coupled in parallel with the laser diode, configured to measure a temperature of a junction of the laser diode and to heat the junction, the sensor configured to heat the junction at least during a non-lasing state of the laser diode; anda controller configured to activate the sensor to heat the junction and maintain the junction temperature within a predetermined temperature range associated with a reduced likelihood of mode hopping occurring for the laser diode.2. The apparatus of claim 1 , wherein the sensor comprises at least a diode.3. The apparatus of claim 1 , wherein the sensor comprises a diode in series with a resistive element.4. The apparatus of claim 3 , wherein the resistive element comprises a thermistor.5. The apparatus of claim 1 , wherein the sensor comprises at least a diode configured to be reverse biased during the lasing state and forward biased during the non-lasing state.6. The apparatus of claim 1 , wherein the sensor comprises at least a diode configured to heat the junction of the laser diode during the non-lasing state and during a portion of the lasing state.7. The apparatus of claim 1 , wherein the sensor is configured to be forward biased during the non-lasing state claim 1 , reverse biased during a first portion of the lasing state claim 1 , and forward biased during a ...

Disk apparatus and head apparatus

A disk apparatus includes a disk, a head, a circuit board, and an abnormality detection circuit. The head includes a plurality of loads, including at least a first load and a second load, associated with writing or reading of data to or from the disk, and a plurality of head terminals corresponding to and connected to the plurality of loads, respectively. The circuit board includes board terminals corresponding to and connected to the plurality of head terminals, respectively, and a preamplifier that applies a voltage to the loads via the plurality of board terminals during writing or reading of the data to or from the disk. The abnormality detection circuit detects a short-circuit between a first board terminal, which is the board terminal connected to the head terminal of the first load, and a second board terminal, which is the board terminal connected to the head terminal of the second load.

MAGNETIC RECORDING SYSTEM USING PATTERN DEPENDENT WRITER HAVING REGISTER PAGES FOR STORING WRITE CURRENTS

A storage system includes a magnetic write head, a magnetic storage medium, a channel circuit comprising a write data output, wherein the channel circuit is operable to process write data to be recorded on the magnetic storage medium by the magnetic write head, and a preamplifier operable to receive the write data from the channel circuit, wherein the preamplifier comprises a number of register pages configured to store pattern dependent write current characteristics for a variety of magnet lengths, and wherein the preamplifier is operable to retrieve the write current characteristics based on magnet lengths and to record data bits on the magnetic storage medium using the write current characteristics. 1. A storage system , comprising:a magnetic write head;a magnetic storage medium;a channel circuit comprising a write data output, wherein the channel circuit is operable to process write data to be recorded on the magnetic storage medium by the magnetic write head; anda preamplifier operable to receive the write data from the channel circuit, wherein the preamplifier comprises a plurality of register pages configured to store pattern dependent write current characteristics for a plurality of magnet lengths, and wherein the preamplifier is operable to retrieve the write current characteristics based on magnet lengths and to record data bits on the magnetic storage medium using the write current characteristics,wherein the channel circuit and the preamplifier operate in a plurality of operating modes, comprising a clocked mode wherein the magnet lengths are determined based on the write data and on a clock signal from the channel circuit, and a channel mode wherein the magnet lengths are determined based on a pattern dependent write page selection signal from the channel circuit.2. The storage system of claim 1 , wherein the preamplifier comprises a pattern detection circuit operable to determine the magnet lengths in the write data claim 1 , and wherein the channel ...

MAGNETIC RECORDING SYSTEM INCLUDING DIFFERENTIATED WRITE CURRENT EMPHASIS SIGNAL GENERATOR CIRCUIT

A storage system includes a magnetic storage medium, a magnetic write head, a channel circuit and a preamplifier. The channel circuit includes a write data input, a differentiated edge emphasis signal generator, a write data output and a differentiated edge emphasis signal output. The preamplifier includes a write data input configured to receive write data from the channel circuit write data output, an edge emphasis signal input configured to receive a differentiated edge emphasis signal from the channel circuit differentiated edge emphasis signal output, and a write current edge emphasis controller configured to generate a write current to the magnetic write head based at least in part on the write data and on the differentiated edge emphasis signal. 1. A storage system , comprising:a magnetic storage medium;a magnetic write head;a channel circuit comprising a write data input, a differentiated edge emphasis signal generator, a write data output and a differentiated edge emphasis signal output; anda preamplifier comprising a write data input configured to receive write data from the channel circuit write data output, an edge emphasis signal input configured to receive a differentiated edge emphasis signal from the channel circuit differentiated edge emphasis signal output, and a write current edge emphasis controller configured to generate a write current to the magnetic write head based at least in part on the write data and on the differentiated edge emphasis signal, wherein the differentiated edge emphasis signal has a 1T setup time and a 1T hold time, wherein 1T comprises a fundamental bit period in the write data.2. (canceled)3. The storage system of claim 1 , wherein the differentiated edge emphasis signal generator comprises a pattern detector configured to identify falling edges and rising edges in the write data that should be emphasized in the write current by the write current edge emphasis controller.4. The storage system of claim 1 , wherein the ...

Multiple Track Detection

An apparatus for reading data includes an array of analog inputs operable to receive analog signals retrieved from a magnetic storage medium, wherein the analog inputs correspond to multiple data tracks on the magnetic storage medium, and wherein the number of analog inputs in the array of analog inputs is greater than the number of data tracks being read, at least one joint equalizer operable to filter the analog inputs to yield an equalized output for each of the data tracks being read, and at least one data detector operable to apply a detection algorithm to the equalized output from the joint equalizer to yield detected values for each of the data tracks being read.

Reducing Offset of a Differential Signal Output by a Capacitive Coupling Stage of a Hard Disk Drive Preamplifier

A preamplifier comprises an input stage and a capacitive coupling stage. The input stage is arranged to receive a differential signal from a magnetic resistor which indicates a magnetic field sensed on a magnetic disk of a hard disk drive (HDD) when the preamplifier is powered on from an off state. The capacitive coupling stage has an input arranged to receive the differential signal from the input stage, a filter comprising a first resistor, a second resistor, a first capacitor, a second capacitor, and switches arranged in parallel with respective resistors, where the switches are closed when the preamplifier is powered on from the off state to an on state. A switch control is arranged to determine that an offset of the differential signal has settled and open the switches based on the determination. 1. A preamplifier comprising:an input stage;a capacitive coupling stage;the input stage arranged to receive a differential signal from a magnetic resistor (MR) which indicates a magnetic field sensed on a magnetic disk of a hard disk drive (HDD) when the preamplifier is powered on from an off state to an on state; one or more inputs arranged to receive the differential signal from the input stage;', 'a filter comprising a first resistor, a second resistor, a first capacitor, and a second capacitor;', 'an amplifier comprises a first input and a second input, wherein the first capacitor is coupled to the first input and the second capacitor is coupled to the second input;', 'a first switch and a second switch in parallel with respective resistors, the first switch and the second switch being closed to short the first resistor and the second resistor when the preamplifier is powered on from the off state to the on state and to ground the first input and the second input of the amplifier;', 'a switch control arranged to determine that an offset of the differential signal has settled and to open the first switch and the second switch based on the determination to cause the ...

Information Storage Apparatus and Method

An information storage apparatus includes a magnetic track, a writer, and a reader, where the magnetic track includes a number of magnetic domains. Each magnetic domain is divided into at least two magnetic regions, and the writer is disposed on the magnetic track, and configured to write information to the at least two magnetic regions of each magnetic domain. The reader, disposed on the magnetic track, is configured to read the written information from the at least two magnetic regions. Therefore, multiple pieces of valid information are written to one magnetic domain of the magnetic track, thereby increasing storage density of the magnetic track, and expanding a storage capacity of the storage apparatus. 1. An information storage apparatus , comprising:a magnetic track comprising a plurality of magnetic domains, wherein each of the plurality of magnetic domains is divided into at least two magnetic regions;a writer disposed on the magnetic track and configured to write information to the at least two magnetic regions of each magnetic domain; anda reader disposed on the magnetic track and configured to read the information written to the at least two magnetic regions of each magnetic domain.2. The apparatus according to claim 1 , wherein all of the at least two magnetic regions of each magnetic domain have a same magnetic field direction when no information is written in.3. The apparatus according to claim 1 , wherein all of the at least two magnetic regions of each magnetic domain are made of materials with different magnetization thresholds claim 1 , and wherein the magnetization threshold is a minimum external magnetic field strength for changing a magnetic field direction of a magnetic region.4. The apparatus according to claim 3 , wherein the writer is configured to:generate a first induced magnetic field; andchange a magnetic field direction of a first magnetic region in the at least two magnetic regions using the first induced magnetic field in order to ...

MAGNETIC DISK DEVICE AND WRITE METHOD

A magnetic disk device includes a disk, a head configured to write data on the disk, and a controller. The controller generates a target trajectory of the head in a circumferential direction for writing to a plurality of sectors in a current track, wherein the target trajectory is based on an actual trajectory of the head for writing to a plurality of sectors in a previously written track that is adjacent to the current track, determines that the previously written track is discontinuous between an initial sector of the previously written track and an end sector of the previously written track by a radial offset, generates a corrected trajectory for writing the plurality of sectors in the current track, and controls a position of the head in a radial direction based on the corrected trajectory while writing to the plurality of sectors in the current track. 1. A magnetic disk device comprising:a disk;a head configured to write data on the disk; anda controller configured togenerate a target trajectory of the head in a circumferential direction for writing to a plurality of sectors in a current track, wherein the target trajectory is based on an actual trajectory of the head for writing to a plurality of sectors in a previously written track that is adjacent to the current track;determine that the previously written track is discontinuous between an initial sector of the previously written track and an end sector of the previously written track by a radial offset;based on the radial offset, generate a corrected trajectory for writing the plurality of sectors in the current track; andcontrol a position of the head in a radial direction based on the corrected trajectory while writing to the plurality of sectors in the current track.2. The magnetic disk device according to claim 1 , wherein the initial sector of the previously written track is adjacent to end sector of the previously written track.3. The magnetic disk device according to claim 1 , wherein the controller ...

SYNTHETIC ANTIFERROMAGNETIC READER

Implementations disclosed herein provide for an apparatus, comprising a synthetic antiferromagnetic reader structure, wherein total moment of a pinned layer is substantially greater than total moment of a reference layer. In one implementation, the pinning strength of the pinned layer is substantially reduced. 1. An apparatus , comprising:{'sup': '2', 'a synthetic antiferromagnetic (SAF) structure, wherein a ratio of total moment MrT of a pinned layer in the SAF structure and total moment MrT of a reference layer in the SAF structure is substantially greater than 1.1, and wherein the pinned layer has a pinning strength substantially lower than 0.9 erg/cm.'}2. The apparatus of claim 1 , wherein magnetic moment (Mr) of the pinned layer is substantially greater compared to magnetic moment (Mr) of the reference layer and thickness of the pinned layer is similar to thickness of the reference layer.3. The apparatus of claim 1 , wherein thickness of the pinned layer is substantially greater compared to the thickness of the reference layer and magnetic moment (Mr) of the pinned layer is similar to magnetic moment (Mr) of the reference layer.4. The apparatus of claim 1 , wherein the ratio of MrT of the pinned layer and the MrT of the reference layer is substantially greater than 1.2.5. (canceled)6. The apparatus of claim 1 , wherein the SAF structure is used in a sensor stack of an MR sensor.7. The apparatus of claim 1 , wherein the SAF structure is used in a pinned bottom shield.8. The apparatus of claim 1 , wherein ratio of magnetic moment (Mr) of the pinned layer and magnetic moment (Mr) of the reference layer is substantially greater than 1.2 and wherein thickness of the pinned layer is similar to thickness of the reference layer.9. The apparatus of claim 1 , wherein pinning strength of the SAF structure is substantially lower than 0.5 erg/cm.10. A method of controlling the pulse width fluctuation (PW50) of a sensor stack by controlling a ratio of total moment MrT of a ...

MAGNETIC DISK DEVICE AND REFRESH PROCESSING METHOD

According to one embodiment, a magnetic disk device includes a disk, a head that writes data to the disk and reads data from the disk, and a controller. The controller is configured to read first data written on the disk, measure a first read error rate of the first data, determine a difference in the first read error rate from a previously determined read error rate of the first data, determine a current read error rate for second data written on the disk based on the difference in the first read error rate from the previously determined read error rate, and determine whether a refresh process is performed on the second data based on the current error rate. 1. A magnetic disk device comprising:a disk;a head that writes data to the disk and reads data from the disk; and read first data written on the disk;', 'measure a first read error rate of the first data;', 'determine a difference in the first read error rate from a previously determined read error rate of the first data;', 'based on the difference in the first read error rate from the previously determined read error rate, determine a current read error rate for second data written on the disk; and', 'based on the current error rate, determine whether a refresh process is performed on the second data., 'a controller configured to2. The magnetic disk device of claim 1 ,wherein the controller is configured to determine whether the refresh process is performed on the second data comprises by determining whether the current error rate exceeds a threshold value.3. The magnetic disk device of claim 1 ,wherein the controller is configured to determine the current read error rate for the second data by adding the first read error rate for the first data to a previously measured read error rate for the second data.4. The magnetic disk device of claim 1 ,wherein the second data are stored in a first portion of a user data area of the disk and the controller is further configured to perform the refresh process on the ...

Circuits and methods for cancelling a reflected wave

Method and circuits for cancelling reflected waves from a load are disclosed. An embodiment of the method includes transmitting a signal to the bad from a current source, wherein a transistor is connected in parallel with the current source at a node. The transistor is biased so that a reflected wave at the node will cause the drain to source voltage of the transistor to increase. The drain current of the first transistor increases by way of channel length modulation when the drain to source voltage increases, the increased drain current cancels the reflected wave.

Adaptive correction of symmetrical and asymmetrical saturation in magnetic recording devices

In one embodiment, a read channel comprises: a preprocessor for receiving a first signal and producing a second signal from the first signal using current values of a positive coefficient, a zero coefficient, and a negative coefficient; an interpolator for producing a third signal based on the second signal; and a slicer for producing a fourth signal from the third signal by estimating a level for the third signal. The fourth signal is at one of three levels consisting of a positive level, a zero level, and a negative level. For every n first signals received by the preprocessor, the current value of one of the positive coefficient, the zero coefficient, and the negative coefficient is adjusted depending on which of the three levels the fourth signal is at.

SLIDER TEST SOCKET WITH CLAMP, AND RELATED ASSEMBLIES AND METHODS OF USE

Described are clamps useful for temporarily holding a slider of a hard disk drive in a test socket for dynamic electrical testing of the slider, as well as related assemblies that include the test socket, a head-gimbal-assembly, a testing assembly, and related methods of use. 2. A clamp of comprising:a stationary left-side frame member at a left portion of the frame, extending from a forward frame member in a length direction toward a rear portion of the frame, anda stationary right-side frame member at a right portion of the frame, extending from a forward frame member in a length direction toward the rear portion of the frame.3. A clamp of comprisinga set of left-side springs on a left side of the clamp, each spring having a central end attached to an axial member and a lateral end attached to the stationary left-side frame member,a set of right-side springs on a right side of the clamp, each spring having a central end attached to an axial member and a lateral end attached to the stationary right-side frame member,the axial member extending along a length-wise axis of the frame and being connected to the springs such that with deflection of the springs the axial member is movable relative to the stationary frame in a direction of a lengthwise axis of the clamp,the rear contact surface being connected to the axial member.4. A clamp of wherein the set of right-side springs includes from 4 to 21 springs and the set of left-side springs includes from 4 to 21 springs.5. A clamp of comprising:a left-side spring extending in the length direction on a left side of the clamp, the left-side spring having a forward stationary end that is stationary relative to the stationary frame, and a rear movable end that connects directly or indirectly to the rear contact surface, anda right-side spring extending in the length direction on a right side of the clamp, the right-side spring having a forward stationary end that is stationary relative to the stationary frame, and a rear ...