ELEMENT SUBSTRATE, PRINTHEAD, AND PRINTING APPARATUS

Technical Field

The invention relates to an element substrate, the print head and the printing apparatus.

Background Art

Traditionally, in order to use the heat energy to discharge the ink from a plurality of ink-jet printing head in the discharge characteristic of the realizing stable, the need to apply the stable voltage of the heater. In the used for printing head element in the substrate, is configured with a plurality of heater and with a plurality of heaters corresponding to a plurality of drive element. Drive element is a field effect transistor, and through the switch to drive the heater. At the same time driving a plurality of the heater under the condition of, a large current is flowed to the ground wiring and to the heater for supplying power to the driving power supply wiring. In this large-current of the supply of the rise and fall of the slider, because the driving power supply and the ground wiring in the wiring inductance between the occurrence of the coupling of the electromagnetic noise, this is a problem.

The print head in the element substrate, in addition to the outside of the heater, is also provided for receiving and processing a high-speed print data of the logic circuit. For this reason, the possibility of the presence of the following: in the ground wiring in the in the occurrence of the above inductance to coupling of electromagnetic noise, the error operation of the logic circuit. Therefore, adopts the structure as follows: in the element substrate and the print head, the heater the ground wiring and for the logical circuit and the component base plate of the ground wiring separation. Therefore, to prevent the driving a plurality of heater when transmitted to the electromagnetic noise for the logical circuit and the component base plate of the ground wiring, and to prevent the misoperation of the logic circuit.

In the used for printing head element in the base plate, according to the recent improvement of Image quality to the requirements of the implementation of the substrate temperature control. In the used for printing head element in the base plate, according to the temperature of the discharged ink discharge velocity and liquid drop will change. Because of this reason, if there is based on the temperature of the base position of the temperature distribution, the temperature distribution is not uniform which will lead to the Image, and the Image quality will be reduced. As the Image of the temperature distribution correction method, for example, in Japan [...] 2014 - 200972 in, through the in the element substrate is arranged in a plurality of auxiliary heaters and heating a particular region in the substrate is suppressed uneven temperature, in order to realize high Image quality. In addition, because the adoption of the element substrate can be in carrying in the auxiliary heater drive element without increasing the number of terminals of the plurality of heating area, it is possible to achieve the reduction of cost of the main body of the printing apparatus.

At the same time drive a plurality of auxiliary heaters of the cases, A (amp) of the order of magnitude of the current flowing through. From the configuration in the printing device on the body of the power supply circuit to the element substrate of the driving power supply wiring and the ground wiring of a wiring length as the length, and the parasitic inductance component becomes larger. In response to the parasitic inductance component driving the auxiliary heaters when under the condition of large electric current flows through, the ring. Because of this kind of ringing, cause for auxiliary heaters of the ground wiring and used for the element substrate of the ground wiring between the increasing in the twinkling of the potential difference. Because the electric potential difference as a driving element of the field effect transistor is turned on, as a result, in the parasitic transistor A (ampere) flows in the order of magnitude of a large current, thereby causing misoperation of the driving element.

Content of the invention

The invention through in mounting the auxiliary heaters and the substrate temperature control of the element substrate in the realization of the logic circuit and the driving element both to prevent the mis-operation of, a higher level of reliability.

According to one aspect of the present invention, to provide a component base plate, comprising: a plurality of printing elements, it is configured to discharge the liquid; a plurality of 1st drive element, with the plurality of printing element relatively set, and is configured to drive the plurality of printing element; a plurality of heating element, and is configured to heat the element substrate; a plurality of 2nd drive element, with the plurality of heating element relatively set, and is configured to drive the plurality of heating element; and delay unit, configured to drive at the same time the plurality of 2nd drive element under a condition, to a predetermined time difference to delay the plurality of 2nd drive element of the drive timing.

According to the another aspect of the invention, claims a print head, comprising: a plurality of printing elements, it is configured to discharge the liquid; a plurality of 1st drive element, with the plurality of printing element relatively set, and is configured to drive the plurality of printing element; a plurality of heating element, it is disposed as the heating element substrate; a plurality of 2nd drive element, with the plurality of heating element relatively set, and is configured to drive the plurality of heating element; and delay unit, configured to drive at the same time the plurality of 2nd drive element under a condition, to a predetermined time difference to delay the plurality of 2nd drive element of the drive timing.

According to another aspect of the present invention, provides a printing apparatus, including: a plurality of printing elements, it is configured to discharge the liquid; a plurality of 1st drive element, with the plurality of printing element relatively set, and is configured to drive the plurality of printing element; a plurality of heating element, it is disposed as the heating element substrate; a plurality of 2nd drive element, with the plurality of heating element relatively set, and is configured to drive the plurality of heating element; and delay unit, configured to drive at the same time the plurality of 2nd drive element under a condition, to a predetermined time difference to delay the plurality of 2nd drive element of the drive timing.

Through this invention, so that the can pass according to the current driving the auxiliary heaters when the rise and drop of the occurrence of the suppressed ringing, the logic circuit and to prevent the misoperation of the driving element.

By the following (reference with photos) typical of the embodiment of the description, other characteristics of this invention will become obvious.

Description of drawings

Figure 1 is the external three-dimensional view of shown according to the present invention of the inkjet printing apparatus of the example of the structure.

Figure 2 is the diagram of shown according to the present invention of the inkjet printing apparatus of the example of the control structure.

Figure 3 is the diagram of the embodiment shown in accordance with the 1st of the example of the structure of the print head.

Figure 4 is the diagram of the embodiment shown in accordance with the 1st of the printing element substrate of the example of the structure.

Figure 5 A and 5 B shows the latch signal delay circuit structure example of the Figure.

Figure 6 is the diagram of the latch signal of the delay circuit shown in the sequence chart.

Figure 7 A and 7 B is shown according to the 1st embodiment of the print head of the sequence chart of the Figure.

Figure 8 is the diagram of the embodiment of the 1st shown according to the equivalent circuit of the print head.

Figure 9 A and 9 B is used for explaining the embodiment according to the 1st working waveform of the plan of the print head.

Figure 10 is the sectional view of the driving element for the operation of the note.

Figure 11 A and 11 B error is used for explaining the operating state of the sectional view of the drive element.

Figure 12 is the chart of the presentation of the parasitic NPN transistor of the drive element of the current characteristics.

Figure 13 is the diagram of the embodiment of the 2nd shown according to the printing element substrate of the example of the structure.

Figure 14 is the diagram of the auxiliary heating data delay circuit showing the structure of an example.

Mode of execution

The following, to the reference with photos to provide the preferred embodiment of the present invention more specific and detailed explanation. However, unless the special note, otherwise this embodiment records the relative component of the configuration and the like are not intended to limit the scope of the invention.

In this specification, the term "printing (print)" includes not only such as character and shape of the meaningful information such as formed, but also the formation of meaningless information. In addition, "printing" also comprising a wide range and whether or not people can be independent of the visually perceived to a print medium in the Image or pattern is formed on the medium of the situation or of the treatment situation.

Similarly, the term "printing medium" include not only the ordinary printing apparatus used in the paper, but also capable of receiving ink comprising a wide range such as cloth, plastic film, metal, glass, ceramic, wood or leather and other things.

In addition, with the definition of "print" similarly, should be broad interpretation of the term "ink" (in the following also referred to as "liquid"). Therefore, "ink" including through the is applied to the printing medium in the Image or Image pattern is formed, the processing of the printing medium or ink processing (for example, the applied to the print medium ink in the colorant cannot be dissolved or solidification) of the supplied liquid.

In addition, unless the special note, otherwise the term "printing element" always includes the nozzle, generating energy used for discharging the ink with the row of the element and of the outlet of the liquid channel.

In addition, unless the special note, otherwise the term "nozzle" generally includes the nozzle, generating energy used for discharging the ink with the row of the element and of the outlet of the liquid channel.

Following the use of the print head element substrate (head substrate) is not only expressed by the silicon semiconductor substrate, but also indicated is provided with the element and the structure of the wiring and the like.

In addition, "on the base plate" is not the only simple means that the top of the element substrate, but also implies that in the element substrate on the surface of the in and near the surface of the inside of the element substrate. In addition, in the invention of the "built-in" does not mean that the substrate surface in a separate element on the simple configuration in order to separate the individual, but imply the use of the semiconductor circuit manufacturing processing element plate integrally formed on and manufacturing these components.

With respect to the most important features of the present invention ink jet print head (hereinafter referred to as the "print head"), of the print head element substrate, on the same substrate to realize a plurality of print element and means for driving these printing element driving circuit. It is evident from the following description, in the print head are integrated in a plurality of element substrate, and these elements are connected in series and the connection structure to the base plate. Therefore, the print head can realize the relatively long printing width. Therefore, not only the print head of the Serial type printing apparatus in common use, but also including the printing width of the print medium with a width corresponding to the entire use of the print head in the printing apparatus. In addition, in Serial type printing apparatus, the printing head also in the use of such as A0 or B0 and the like of the large size of the printing medium used in large format printers.

Therefore, first of all, note the use of the invention of the print head of the printing apparatus.

SUMMARY of printing apparatus

Figure 1 is the external three-dimensional view of the use of the present invention showing a representative embodiment of ink-jet print head (hereinafter referred to as the print head) to carry out the printing of the printing apparatus of the SUMMARY of the structure.

As shown in Figure 1, in ink-jet printing apparatus (hereinafter referred to as the printing apparatus) 1 in, the carriage 2 mounted on the inkjet ink through according to the discharged ink jet print head to print (hereinafter referred to as the print head) 100, and by making the carriage 2 in the direction of the arrow symbol A reciprocating movement to print. Such as the printing of the printing medium P such as via the sheet supply mechanism 5 to feed, and delivery to the print position, and through the ink from the printing position of the print head 100 is discharged to the printing medium P to print.

In the printing device 1 and a carriage 2 not only carries the print head 100, but also to the print head is provided with a containing 100 supply the ink reservoir 6. With respect to the carriage 2 installation/remove the reservoir 6.

Figure 1 indicated by the printing apparatus 1 can carry out color printing, and to this end, will hold the magenta (M), cyan (C), yellow (Y) and black (K) ink cartridge mounted to the four carriage 2. The four ink cartridge can be independent of the mounting/dismounting.

According to the present invention print head 100 using a heat energy discharge ink-jet mode. Therefore, including the electrothermal transducer. For each nozzle set the electrothermal transducer, and through according to the print signal to a corresponding electrothermal transducer applying a pulse voltage to discharge ink from the corresponding nozzle. Note, the printing apparatus is not limited to the above-mentioned Serial type printing apparatus, and can be suitable for the so-called of the entire printing apparatus, in which in the entire printing apparatus, a print medium in the conveying direction, the configuration of the nozzle is disposed in the transverse direction of the printing medium of the print head (the whole breadth of the head).

Figure 2 is the block diagram of shown Figure 1 shown in the control structure of the printing apparatus.

As shown in Figure 2, controller 10 by the MPU 11, ROM 12, application-specific integrated circuit (ASIC) 13, RAM 14, system bus 15 and A/D converter 16 and the like. ROM 12 stores various types of control sequence corresponding to the program, the required table and other fixed data. ASIC 13 produce and is used for the carriage motor M1 of the control, the conveying motor M2 and the control of the print head 100 of the control of the control signal. RAM 14 is used as the Image data included in the regional or program execution for the work area and the like. The system bus 15 the MPU 11, ASIC 13 and RAM 14 are connected with each other, and carry on the reception of the data. A/D converter 16 from the following sensor group of the input analog signal, to its A/D conversion, and the generated digital signal is supplied to the MPU 11.

In addition, in fig. 2 in, a host device 41 such as a PC as Image data of the source of supply of such as the external information processing apparatus. Via the interface (I/F) 42 of packet communication to a host device 41 and printing apparatus 1 between the Image data, such as the command and status of the transmitting and receiving. Note, can adopt the following structure: also includes a USB interface as the single interface with the network interface 42, and enables continuous transmission received from the host to the location data and the raster data.

The switch bank 20 by the power switch 21, print switch 22 and the resume switch 23 and the like.

The sensor group 30 is used for detecting the state of the sensor group, and by the position sensor 31 and the temperature sensor 32 and the like. In addition, for detecting the residual quantity of ink of the photoelectric sensor.

The carriage motor driver 43 is for driving the carriage motor M1 in order to make the carriage 2 in the direction of the arrow symbol A reciprocating scanning carriage motor driver. The conveying motor driver 44 is used for driving is used for transporting the printing medium P of the conveying motor M2 of the conveying motor driver.

ASIC 13 in the use of the print head 100 for printing and scanning, in direct access RAM 14 at the same time storage area of the transmission and is used for the print head driving heating element (ink for discharge heater) of the data. In addition, in the printing device is disposed on the LCD or LED by a display unit as a user interface.

Then, what constitutes used as the above-mentioned structure of the print head of the printing apparatus in the liquid discharge head of the head substrate (element substrate) of the embodiment.

1st embodiment

Figure 3 shown according to the invention of the 1st embodiment of the printing apparatus 1 in the print head 100 of the example of the structure. The print head 100 is configured to include the print element substrate 101, the flexible base plate 106 and a printed circuit board 107. The print element substrate 101 via the flexible substrate 106 with the printed circuit board 107 is electrically connected. The printed circuit board 107 through cable 108 with the configuration in the printing device 1 on the body of the head of the control base plate 109 is electrically connected.

A detailed description of the printing element substrate 101. The print element substrate 101 is configured to include a plurality of print element 102, a plurality of drive element 103, a control gate 104, logic circuit 105, auxiliary heaters 115 and drive element 116. The embodiment of the invention, the print element substrate 101 by the semiconductor layer, the wiring layer and the insulating layer.

The printing element 102 is used for heating and discharge ink printing element group. Drive element 103 is used for driving the printing element 102 of the printing element to drive the element group. In response to the drive element 103, mainly use the field effect transistor (FET: Field Effect Transistor). The control gate 104 is used for a control drive element 103 control of pressure.

Logic circuit 105 is used for transmitting the control signal to the control gate 104 of the logic circuit. Logic circuit 105 is mainly composed of a used for keeping print data of the latch circuit, the shift register circuit and the driving element for generating an on time of the heat enable signal (HE) of HE generating circuit. Later will describe the details of these circuit. Logic circuit 105 receives from the head control IC 120 sends to the various signals. Here the various signal with the data signal (DATA), clock signal (CLK) and the latch signal corresponding to (LT). Note, head control IC 120 is disposed in the head control base plate 109 on. The auxiliary heater 115 is used for the print element substrate 101 of a specified area of the heating of the heater (heating element), and through the heating the print element substrate 101 is heated to the extent of not discharging ink. The driving element 116 is used for driving the auxiliary heaters 115 of the light source of the driving element. In this embodiment, it is assumed that for the printing element driving element 103 and for auxiliary heaters drive element 116 is arranged in the same on the semiconductor layer. In addition, in this embodiment, it is assumed that the driving element 103 and 116 use the N-type field effect transistor.

The printing element 102 is connected to one end of the for supplying the driving power supply of the power supply (VH) printing element, and another end is connected to the as a driving element 103 of the FET drain electrode post. Similarly, for the auxiliary heater 115 and printing element 102, will be connected to one end of the print element power supply (VH), and another end is connected to the FET (driving element 116) of the drain electrode post. In addition, will be used for the printing element driving element 103 source terminal and for auxiliary heaters drive element 116 is connected to the print element the ground wiring (GNDH), and the base-plate terminal (back gate) connected to the base the ground wiring (VSS). The control gate 104 of the power supply is connected to the control gate power supply wiring (VHT), and the logic circuit 105 of the power supply is connected to the logic circuit power supply wiring (VDD). The control gate 104 and logic circuit 105 is connected to the base plate and the ground terminal (VSS) ground wiring.

Will be used for driving the printing element 102 and the light source of the 115 of the printing element power supply (VH) and the print element the ground wiring (GNDH) connected to the head of the control base plate 109 on the power supply circuit 110. In the power supply circuit 110 is generated in the power supply, and through cable 108, the printed circuit board 107 and the flexible base plate 106 and supply it to the print element substrate 101. The printing element the ground wiring (GNDH) and the base plate the ground wiring (VSS) in the print head 100 is separated in, and in the head of the control base plate 109 on the short-circuit. Therefore, to prevent the driving a plurality of print element 102 and the light source of the 115 when the electromagnetic noise generated by the transmission to the base plate of the ground wiring (VSS), and to prevent the misoperation of the logic circuit.

There is as follows: in the print head 100 and head control substrate 109 of the printing apparatus 1 of the configuration of the restrictions in the resulting cable 108 a wiring length of greater than or equal to 1 m under the condition of the, accompanying the parasitic inductance of the transmission of the. In particular, only the cable 108 in, to hundreds of nH - 1 μH orders of magnitude. In order to reduce due to the cable 108 large parasitic inductance generated by the VH - GNDH ringing, in the printed circuit board 107 on, in VH and GNDH is arranged between the capacitor 114. In response to capacitor 114, such as the use of several hundred μF electrolyte capacitor.

Figure 4 is the diagram of the embodiment of the 1st shown according to the print element substrate 101 of the example of the detailed structure. Note, in fig. 4 in, in the presence of a plurality of the same elements of a structure under the situation, the additional suffix added to the Figure mark. The latch circuit 201 is used to keep the print data of the print data shift register/latch circuit, and using the latch signal (LT) to make the printing data. Logic circuit 203 is used for in units of time-sharing startup control gate 104 for block selection logic circuit. HE generating circuit 204 is used to generate the driving element 103 on time of the heat enable signal (HE) of HE generating circuit. HE pulse delay circuit 202 is used to delay heat enable signal (HE) can heat makes the pulse delay circuit, and the delay of transport heat enable signal. The control gate 104 through the print data, the block selection signal and the heat enable signal (HE) logic area, to control is switched on (ON) also is disconnect (OFF) printing element driving element 103.

The latch circuit 209 is used to keep the vice-heating vice-heating data of the data latch circuit. The shift register circuit 206 is used for transmitting the auxiliary heating vice-heating data of the data shift register circuit. The latch signal delay circuit 208 is to make the latch signal delay several ns to several hundred ns of the latch signal delay circuit. The set of the plurality of latch circuit 209 based on the latch signal delay circuit 208 and the delay of the latching signal [...] (LT - 1, LT - 2, ..., LT - m) to store auxiliary heating data. Therefore, the auxiliary heating data stored in the plurality of latch circuit 209 in each of the latch circuit in the timing is delayed by a few ns to several hundred ns. For auxiliary heaters drive element 116 is turned on or off at the same time, to the auxiliary heating data stored in the latch circuit 209 in. Therefore, to drive a plurality of auxiliary heaters 115 of each auxiliary heaters in the timing of the number of delayed ns to several hundred ns.

Figure 5 A and 5 B shows the latch signal delay circuit 208 of the example of the Figure. In fig. 5 A in, latch signal delay circuit 208 by a plurality of inverting circuit to form, and by aiming at the level corresponding to the delay time of the inverter circuit × inverting circuit to determine the number of stages of the latch signal delay circuit 208 of the overall delay time. Figure 5B is the chart of shown latch signal delay circuit 208 individual example. In fig. 5 B in, latch signal delay circuit 208 by a plurality of trigger circuit, and through the clock signal cycle × of the trigger circuit to determine the progression of the latch signal delay circuit 208 of the overall delay time.

Figure 6 is the chart of shown Figure 5 B latch signal delay circuit 208 of the sequence chart. The embodiment of the invention, the print element substrate 101 performs time-sharing driving, wherein the row of the printing is divided into a predetermined number of blocks, and in turn drives the auxiliary heater 115. Here, line time expressed for the Image row or a column (collectively referred to as line) printing to the print medium on the time. Block time degrees of said printing unit the time required for the a block, and a line time and printing the above-mentioned predetermined number of blocks required time (the predetermined number of blocks of time) corresponding to. In addition, the latch signal (LT) is used for the designation of a block signal.

Figure 7 A shown does not include the print head according to the present invention driving the light source of the delay element (latch signal delay circuit 208) of the time sequence chart of the situation. On the other hand, Figure 7 B shown against in this embodiment of the print head 100 (including according to the present invention driving the light source of the delay element) of the sequence chart.

In order to heat a nozzle the very small amount of ink (for example, a picoliters) in order to discharge it, printing element 102 drive period can be relatively short hundreds of n (nano) seconds. Therefore, by high-frequency heat enable signal (HE) to drive the printing element 102. On the other hand, because the auxiliary heaters 115 needs to the large thermal capacity of the element substrate of a specified area of the heating and the maintenance of the heating, and therefore require the driving time is prolonged dozens of μ (micro) seconds to several hundred m (Howe) seconds. As the causes, through the relatively low frequency signal to drive the auxiliary heaters 115. The embodiment of the invention, by the use with specific heat enable signal (HE) of the frequency of the low frequency of the latch signal vice-heating storage of data to carry out the auxiliary heaters 115 of the drive. In addition, the structure makes the used for the delay in the embodiment of the printing element substrate 101 of the latch signal in the latch signal delay circuit 208 to gradually delay storage auxiliary heating data 1 - m of the timing. By this structure, prevents the driving auxiliary heaters 115 when the current in the VH dramatically a rising edge or a falling edge, and prevent the driving element 103 in the false operation.

In this embodiment in the structure of the light source of the existence of the 115 of electric current and the print element 102 of the current changes from the advantages of timing do not overlap. In the use of a latch signal (LT) will print the data stored in the latch circuit reliably after the in, requires the use of a heat enable signal (HE) to drive the printing element 102. For this reason, in response to the latch signal (LT) of the rising edge and the heat enable signal (HE) rising edge, n (nano) configuration hundreds of seconds timing margin (offset). Therefore, through the latch signal (LT) driven by auxiliary heaters 115 of the current and through the heat enable signal (HE) driving of the printing element 102 changes from the current timing do not overlap. In the printing element 102 in, at most about 4 A (amp) of great current flows through the. In addition, in the light source of the 115 in, at most about 1.5 A (amp) of great current flows through the. For this reason, the drive at the same time under the condition of change timing reliably not overlap is important.

Traditionally, if the printing element substrate of the temperature lower than the target temperature, and driving the auxiliary heaters is a work, and if the temperature is higher than the target temperature, together with the stops driving. For this reason, vice-heating data all together at the same time a high possibility is rewritten, and rewrites the electric current peak tends to become higher. For this reason, in the write data as vice-heating timing of a latch signal (LT) rising edge, current flows immediately, and in the printing element substrate in the logic circuit to the power supply the instantaneous voltage drop. If the voltage drop, its become logic circuit the mis-operation of reasons.

In this embodiment in the structure of the, there can inhibit the rewriting of the latch circuit 209 when the rewriting of the data flow of the current peak value of the advantages. In this embodiment, because the structure is such that the latch signal delay circuit 208 to reliably enable the rewrite vice-heating data timing offset, so can inhibit the rewrite current peak. That is to say, through to each of the secondary heater 115 is offset to make the rewrite vice-heating the timing of data dispersion. As a result can make the logic power supply a minimum voltage drop across. Therefore, can improve the logic circuit will not take place and the high reliability of the misoperation of the printing element substrate. In other words, as shown in Figure 7 B shown, can be arranged to latch the signal delay circuit 208 to prevent Figure 7 A shown over-current flow. Accompanying this, can prevent the faulty operation of the logic circuit.

To provide a more detailed explanation. Figure 8 is the diagram of the embodiment shown in accordance with the 1st of the print head 100 of the equivalent circuit. In addition, Figure 9 A and 9 B shows the waveform of the print head of the work plan. Figure 9 A amplifying a graph 7 A part (not provided with the auxiliary heaters of the driving delay component), and Figure 9 B amplifying a graph 7 B a portion of the (is provided with a pair of heater driving delay of components). -use maps 8, Figure 9 A and Figure 9 B, note the latch signal delay circuit 208 of the effect. Figure 8 shown in the arrow symbol said vice-heating driving and stopping time t1 (reference view 6) of the printing element substrate 101 of VH current path.

At the time t1, produce two current path - by the solid-line representation of the current by the dashed line represents the current X and Y (reference view 8). X is the current flow between the GNDH VH and the current, and is driving the auxiliary heaters 115 when the normal current path. Current Y is in VH and the current flowing between the VSS, and as a driving element is in the on-state of FET from into the off state when the leakage current. In particular, current Y is due to the FET of a depletion layer in the capture of the leakage current of positive charge

Figure 10 is the diagram of the drive element (FET) shown at the time t1 cross section. At the time t1, the drive element from the on state into the off state, the drain terminal from 0 V gradually increase to VH (32 V) of the voltage. The drive element of the PN displaced by the expansion of the depletion layer, and the driving element of the [...] N diffusion layer of positive charge into the depletion layer, and a source of positive charge to the P diffusion layer from 0 V (VSS). Therefore, VSS between VH and the instantaneous flow current Y.

As shown in Figure 8, and VH VSS through current between the Y moment between the GNDH from VH and capacitor 114 supply, therefore its ultimate flow to the GNDH. Therefore, the current Y flows into the VSS and GNDH is short circuited head control substrate 109 in. Because at this time the current Y through the parasitic inductance of the cable 108, therefore the current Y included in the frequency component of the larger, the larger the ringing is generated. Figure 9 A shown is not provided with a latch signal delay circuit 208 under the situation of the voltage waveform of the GNDH. As in the light source of the 115 of the sharp decline in driving and stopping the current, therefore, current Y comprises a high-frequency component. Therefore, in the negative side of the GNDH generating a large ringing. Figure 9 A moment t2 shows this state.

Since the ringing, and resulted in the GNDH and as a driving element (FET) of the basic potential of momentarily in the VSS producing negative potential difference. In the potential difference exceeds the driving element (FET) of the forward voltage of the parasitic transistor of the VFP (GNDH voltage<- VFP), the drive element (FET) of the parasitic NPN transistor turns on, and the large current generating, so in the incorrect operation in the drive element.

Figure 11 A and 11 B shows the driving element (FET) of the parasitic NPN transistor into the "on" state and misoperation of the state of the diagram. Figure 11 A shown auxiliary heaters drive element (used for auxiliary heaters the driving element of the misoperation of the (current)), and Figure 11 B shown printing element driving element (used for printing the drive element of the misoperation (over-current)). Here, the light source of the driving element and printing element driving element is the same structure, and because the GNDH common, therefore the parasitic NPN transistor into the "on" state in response to the incorrect operation of the two.

Figure 12 is the chart of the parasitic NPN transistor showing current characteristics of the current. In the GNDH voltage exceeds the forward voltage of the VFP (GNDH voltage<- VFP), current to index mode to increase. The large current in the VH - - FET drain electrode post printing element of - FET source terminal - GNDH path, and VH - the auxiliary heaters of - FET drain electrode post - FET source terminal - GNDH flows in the path. Therefore, the electric current to flow to the print element 102, thereby resulting incorrect printing operation and damage to the printing element. In addition, the flow of current to the light source of the 115, thereby causing the element substrate of the abnormal temperature rise.

Figure 9 B shown in setting up according to the embodiment of the latch signal delay circuit 208 under the situation of the voltage waveform of the GNDH. Since the latch signal delay circuit 208 can inhibit the light source of the 115 of the driving and stopping of the drastic drop in current, so the electric current Y does not include the high-frequency component. Its result can be according to the current Y to inhibit the negative side to the GNDH of large ringing. By this, the potential difference between the VSS GNDH and stopped for more than the driving element of the parasitic transistor (FET) of the forward voltage of the VFP, and the driving element (FET) stop of incorrect operation. Figure 9 B moment t2 shows this state. In fig. 9 B moment t2, GNDH voltage in the vicinity of the substrate potential (VSS).

Through this embodiment, the print head can prevent from auxiliary heaters when driving the logic circuit and to prevent the misoperation of the misoperation of the driving element of the two, and can realize high reliability.

2nd embodiment

Figure 13 is the chart of shown according to the invention of the 2nd embodiment of the printing element substrate 101 of the example of the detailed structure. With the 1st embodiment is different in that: is provided with a plurality of different delay time vice-heating data signal delay circuit 1201 - a, 1201 - b and 1201 - c. Note, Figure 13 shown vice-heating of data signal delay circuit 1201 the number of are given as examples only, and the number of the print element substrate according to the configuration of the structure. Other structure is the same as with the 1st embodiment, therefore omit its description.

The embodiment of the invention, vice-heating data signal delay circuit 1201 receiving from the latch circuit 209 output signal as input, and outputs it is delayed a predetermined delay time of the delay data signal.

Figure 14 shows the auxiliary heating data signal delay circuit 1201 - a, 1201 - b and 1201 - c of the example. In fig. 14 in the example of the configuration of a plurality of inverting circuit, and by changing the number of stages of the inverting circuit, can make with the auxiliary heating data signal delay circuit corresponding to the delay time different.

Through this embodiment, with the 1st embodiment similarly, can prevent the vice-heating current rise rapidly along the occurrence of or the falling edge, and can prevent the misoperation in the drive element.

Other embodiments

The embodiment of the invention can also be realized through the following method, namely, through the network or various storage medium will be the implementation of the above embodiment of the function of the software (program) to provide to the system or device, the system or device of the computer or central processing unit (CPU), a micro processing unit (MPU) read out and the implementation of the method of the procedure.

Despite the reference example embodiment illustrates the invention, but it should be understood, the invention is not limited to the disclosed exemplary embodiments. The scope of the attached claims with the interpretation of the most wide, in order to include all such modifications, equivalent structures and functions.