PIEZOELECTRIC ELEMENT DRIVING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a piezoelectric element driving circuit with a high efficiency which uses a piezoelectric element as an actuator for mechanical operation in a small electronic device. SOLUTION: The piezoelectric element driving circuit having a high efficiency is made by composing a pulse width modulator with a digital circuit which makes its static current consumption approximately zero by modulating a random signal waveform with a pulse width modulation, and inputting this pulse- width-modulated signal to a transformer primary winding having a predetermined step-up ratio, and connecting an output signal from this transformer secondary winding to the piezoelectric element, and enabling to adapt a step-up winding transformer using a core material having high conversion efficiency since its switching frequency is high.