Voice coil motor control apparatus for use in disk drives

摘要

Disclosed herein is a system for applying a power-supply voltage to the voice coil control circuit provided in a disk drive and designed to drive the head actuator provided in the disk drive. The power supply circuit of the disk drive outputs a voltage that corresponds to the power-supply voltage applied from a host system. A voltage step-up circuit is provided, which increases the output voltage of the power supply circuit. A switching circuit is provided, which selects the increased voltage output from the voltage step-up circuit when a large current needs to be supplied to the voice coil motor incorporated in the disk drive. The switching circuit selects the output voltage of the power supply circuit when a relatively small current needs to be supplied to the voice coil motor.