| 摘要 |
A drive waveform signal as a reference of a drive signal to be applied to a piezoelectric element is power-amplified, and the drive signal after passing through a coil is applied to the piezoelectric element. A resonant circuit is formed of the coil and the piezoelectric element, and a resonant peak is suppressed by performing a phase advance compensation of the drive signal and by performing a negative feedback. At this time, the degree of suppression of the peak is adjusted so that a slight reverse voltage is generated. Since this can eliminate residual distortion of the piezoelectric element by the reverse voltage, even when driving is performed at a high repetition frequency, the original amount of deformation can be ensured. Besides, the circuit does not become complicated.
|
