Patent attributes
A driving circuit for a capacitive load includes a driving signal generating unit that generates a driving signal for driving the capacitive load by using a pair of driving transistors. A power source voltage generating unit generates high-voltage and low-voltage power source voltages that are higher and lower, respectively, than the voltage of the driving signal and applies the voltages to collectors of the driving transistors. The power source voltage generating unit includes a pair of power source transistors and a capacitor. The low-voltage power source voltage is generated in an output side of the power-source transistor pair as a voltage that is in a voltage region lower than that of the driving signal and follows the driving signal. The high-voltage power source voltage is output from a high-voltage terminal of the capacitor, is in a voltage region higher than that of the driving signal, and follows the driving signal.