Switched boost voltage generator for actuator retract in disk drive

摘要

A voltage boost circuit within a hard disk drive is realized by switching a center tap node of a three phase spindle motor to ground during a power down sequence, thereby employing inductance of the spindle motor as a voltage boost inductor. The boosted voltage is rectified and stored in a capacitor for use, e.g. to control a source transistor of an actuator driver during an actuator retract operation.