ULTRASONIC VIBRATOR DRIVING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic vibrator driving apparatus which can be comprised of simple circuits without complicated circuit configuration and operates with stable performances. SOLUTION: The ultrasonic vibrator driving apparatus comprises: an input section for inputting an electric signal of an audible frequency band; an oscillation circuit 102 for generating a carrier signal of an ultrasonic frequency band; a sawtooth wave generation circuit 103 for generating a sawtooth wave signal with the carrier signal as a criterion; a pulse width modulation circuit 104 for generating a pulse width modulation signal corresponding to a signal level of the input signal from the sawtooth wave signal based on the comparison result of the signal level between the sawtooth wave signal and the input signal of the audible frequency band, and a high-output amplifier circuit for driving an ultrasonic vibrator 110 in response to the modulation signal and converting the input signal of the audible frequency band into an acoustic signal. COPYRIGHT: (C)2005,JPO&NCIPI