Abstract: A drive circuit for energizing the winding of a stepper motor includes a first amplifier circuit which receives a unipolar input signal and depending upon the amplitude couples a positive or negative voltage potential to one terminal of the winding. A second amplifier circuit also receives the input signal and applies the same polarity voltage potential to a differentiating circuit. The differentiating circuit operates a transistor switch to couple for a predetermined period of time, a voltage potential of opposite polarity but equal in magnitude to that coupled to the first terminal of the winding, to the second terminal thereof. The application of the double voltage to the winding causes a rapid torque buildup and great acceleration to the stepper motor for a short period of time. The differentiating circuit includes a capacitor having a predetermined time constant which controls the period of time the opposite polarity voltage potential is applied to the second terminal of the winding.