CIRCUIT FOR DRIVING A PIEZOELECTRIC ACTUATOR

摘要

A circuit for controlling a volatile material emitting device includes a piezoelectric pump having an impedance (168) connected in series with a piezoelectric element (62). The impedance and the piezoelectric element form a tank circuit having a resonant frequency. A digital driver (164) is connected to the piezoelectric pump, and first and second comparators (192, 194) are coupled between the digital driver and the tank circuit. The comparators detect a parameter of power applied to the piezoelectric pump by the digital driver to operate the piezoelectric pump at a mechanical resonant frequency thereof.