Disclosed are an ultrasonic linear motor and a method of driving the same. The ultrasonic linear motor includes a vibrator including an elastic portion and a first piezoelectric element and a second piezoelectric element which are disposed on two surfaces of the elastic portion, a moving shaft coupled to the vibrator and moved according to a displacement of the vibrator, a mover inserted into and coupled to the moving shaft, and a controller which applies a first driving pulse and a second driving pulse to the first piezoelectric element and the second piezoelectric element, wherein a frequency of the first driving pulse and a frequency of the second driving pulse are set to a frequency between a resonant frequency at which an impedance is minimum and an anti-resonant frequency at which the impedance is maximum.

A piezo actuator system includes a piezo actuator; and a driving circuit configured to apply a pulse width modulation (PWM) voltage waveform to the piezo actuator. An envelope of the PWM voltage waveform includes a first period in which a first voltage rising with a first slope is applied, a second period in which a second voltage rising with a second slope is applied, and a third period in which a third voltage rising with a third slope is applied. The third slope is greater than the second slope.