Patent ID: 7571989

Claim:
A driving circuit of a droplet ejection head which, by supplying an analog driving signal to a driving element, ejects a droplet from a nozzle provided in correspondence with the driving element, the droplet ejection head driving circuit comprising: a driving signal generation unit that generates at least a first analog driving signal for ejecting a droplet from the nozzle, and at least a second analog driving signal for vibrating a liquid surface of ink in the droplet ejection head, and selectively outputs either of the analog driving signals; a pulse modulation unit that pulse-modulates the analog driving signal output from the driving signal generation unit and outputs a digital signal; a switching signal generation unit that generates a switching signal; an amplification unit that amplifies the digital signal by switching in accordance with the switching signal, and supplies the amplified digital signal to the driving element; and a frequency-setting unit that sets a switching frequency of the switching signal in accordance with a frequency selection signal, the frequency selection signal corresponding to the analog driving signal that is being output from the driving signal generation unit.