Patent ID: 8649537

Claim:
A drive device for performing a pulse modulation of an input signal and outputting an output signal for driving a capacitive load; the drive device comprising: switching driver for including a charging switching element for charging the capacitive load and a short-circuiting switching element for short-circuiting between both terminals of the capacitive load to discharge the capacitive load, and operating the charging switching element and the short-circuiting switching element to output the output signal, the capacitive load being driven by a signal obtained by performing the pulse modulation of the input signal; and driving controller for controlling the switching driver based on the pulse-modulated input signal so as to repeatedly perform a charging phase that alternately repeats a phase charging the capacitive load and a phase not charging the capacitive load, and a discharging phase that alternately repeats a phase discharging the capacitive load by short-circuiting between both terminals of the capacitive load with the short-circuiting switching element and a phase not discharging the capacitive load, wherein the driving controller controls so as to change over from the charging phase to the discharging phase or from the discharging phase to the charging phase when a slope of the input signal changes.