Motor driver circuit, positioning device and hard disk apparatus using same, and motor driving method

Abstract

Disclosed herein is a motor driver circuit including a first output terminal to be connected to a first end of a to-be-driven motor via a sense resistor, a second output terminal to be connected to a second end of the motor, an error detector that generates an error signal, an A/D converter that obtains a digital signal, a compensator that generates a voltage command value, a D/A converter that converts the voltage command value to an analog control signal, a pulse width modulator that generates a first pulse and a second pulse, and an output stage that generates a first driving voltage and a second driving voltage. During a first mode, the compensator uses the error signal obtained by the A/D converter at a negative edge timing of the first pulse, for the error signal at a positive edge timing of the second pulse.