To perform retract operation control at high precision by preventing characteristic degradation or ASO breakage caused by the thermal loss of a power switch element at cutting off a power supply.

A first operation in which an upper side power switch element is turned on to be shorted to a power supply side and a second operation in which a lower side power switch element is turned on to be shorted to the ground potential side of a circuit are alternately performed by a brake control circuit that operates at a voltage of a counter-electromotive force that is generated by a motor coil at cutting off a power supply. A drive output stage of 3-phase DC motor rotates a magnetic disc, a VCM driver drives a voice coil motor for controlling a magnetic head, and a control circuit is provided for an output pre-driver and VCM driver. The reverse braking operation for unloading the magnetic head from the VCM driver is performed, and when the operation voltage generated at the 3-phase DC motor coil reaches a prescribed voltage, such operation as switching to GND brake for applying ground potential to both ends of the voice coil is performed a plurality of times in retract operation.