In a capacitive element driving apparatus which changes, by an output
circuit, the electrode potentials of the electrostatic capacitive element
of a transducer forming a capacitive load such as a piezoelectric member
to drive and control the electrostatic capacitive element, when the
electrode potentials start changing and simultaneously change in the same
direction by the function of a same-direction detection circuit, the
potentials to be applied to the electrodes are controlled with a high
impedance. While a portion between the electrodes of the electrostatic
capacitive element of the transducer is being charged or discharged, the
potentials to be applied are controlled with a low impedance lower than
the high impedance.