Patent ID: 7850265
Filing Date: 2010-12-14
Classification: B41J,H04R

Abstract:
1. A capacitive load driving circuit which applies a driving signal to a capacitive load and drives the capacitive load, the capacitive load driving circuit comprising: an operational amplifier outputting a difference signal of a signal inputted to an inverting input terminal and an analog driving signal inputted to a non-inverting input terminal, and setting a loop gain; a pulse width modulator pulse-width-modulating the difference signal outputted by the operational amplifier, and outputting resultant digital signal; a digital voltage amplifier amplifying a voltage of the digital signal; a first filter smoothing a digital signal outputted by the digital voltage amplifier, and supplying a smoothed signal to the capacitive load as the driving signal; an impedance converting circuit converting an impedance of an output signal of the first filter; and a first feedback circuit feeding-back the driving signal, which is outputted from the first filter, to the inverting input terminal of the operational amplifier via the impedance converting circuit.