Disclosed is a piezoelectric actuator drive unit that includes a piezoelectric actuator drive amplifier and a piezoelectric actuator drive unit power supply. Combinations of high and low signal levels of a first control signal, which controls the supply voltage and amplifier bias voltage of the piezoelectric actuator drive amplifier, and a second control signal, which controls the driving force of the piezoelectric actuator drive amplifier, are associated with a haptic feedback function, a receiver function for generating an audio output, and a speaker function for generating music or the like. Thus, the piezoelectric actuator drive unit, which vibrates a piezoelectric actuator, is adapted to the haptic feedback function, the receiver function, and the speaker function, and can optimize its power and drive amplifier characteristics.