DRIVING DEVICE AND DRIVING METHOD OF CAPACITIVE LOAD AND LIQUID JET PRINTING APPARATUS

摘要

A driving device of a capacitive load includes a modulator that executes pulse modulation on a drive waveform signal. An inductor performs low-pass filtering on the modulated drive waveform signal and outputs the low-pass filtered signal as a drive signal towards a load capacitor as the capacitive load. A load selection control circuit selects a load capacitor and a dummy load capacitor to be connected to the inductor so that a sum of the capacitances of the selected load capacitor and dummy load capacitor is kept within a predetermined range. A feedback circuit executes a filtering process on the drive signal so that a frequency characteristic of a passing band of the drive signal becomes substantially flat. The resulting signal is provided to the modulator as a feedback signal. The modulator executes the pulse modulation on a difference value between the drive waveform signal and the feedback signal.