| 摘要 |
<p>A capacitive load driving circuit includes: a drive waveform signal generator that generates a drive waveform signal; a subtractor that outputs a differential signal between the drive waveform signal and a feedback signal; a modulator that pulse-modulates the differential signal and outputs a modulated signal; a digital power amplifier that amplifies the power of the modulated signal and outputs a power-amplified modulated signal; a smoothing filter that is constructed by connecting an inductor and a capacitive load with a wire, smoothes the power-amplified modulated signal, and outputs a drive signal of the capacitive load; a compensator that causes a phase to precede the drive signal; and an attenuator that attenuates signal amplitude in a band at least including a modulation frequency of the modulated signal, wherein a signal output from a connecting point between the inductor and the wire is made to pass through the compensator and the attenuator and is then used as a feedback signal to the subtractor.</p> |
