ELECTRONIC CONVERSION DEVICE FOR CONVERTING ACOUSTIC SIGNAL TO SEMIDIGITAL SIGNAL, INDICATOR HAVING THE SAME, AND METHOD FOR BIDIRECTION COMMUNICATION BY SOUNDWAVE

PURPOSE: An electronic conversion device for converting acoustic signals to semi-digital signals, an indicator having the same, and a bidirectional communication method using a sonic wave are provided to generate sonic waves and convert the sonic waves to a logic voltage for controlling a microprocessor for exchanging all kinds of data by the sonic waves between two separated objects by simply adding a comparison circuit. CONSTITUTION: An electronic conversion device(20) for converting acoustic signals to semi-digital signals includes an acoustic generator circuit(22) incorporating a piezoelectric vibrator(P3) in addition to a reference voltage supplying element, and a comparison element which compares a voltage generated by the piezoelectric vibrator when obtaining a sonic wave with a reference voltage and generates a semi-digital signal when the voltage generated by the piezoelectric vibrator exceeds the reference voltage. © KIPO 2002 ...