| 摘要 |
PURPOSE:To drive a piezoelectric speaker at the voltage twice the source voltage by applying driving waves deviated of phases by 180 deg. to the piezoelectric speaker. CONSTITUTION:Pulses 7 are inputted to an output inverter 11, and pulses deviated of phases by 180 deg. from pulses 7 are inputted to an output inverter 10. The driving waves to be applied to a piezoelectric speaker 2 are the same as a voltage waveform 19, and is the AC voltage waveform having a potential difference twice the electromotive force (e) of an electric power source 1. |
