Disk drive comprising oscillators and counters for sensing current in a voice coil motor

摘要

A disk drive is disclosed comprising a voice coil motor (VCM) driver including an H-bridge driver having a first sense resistor connected in series with a supply voltage and a second sense resistor connected in series with ground. First and second amplifiers amplify the voltages across the first and second sense resistors, wherein the output of the amplifiers drive respective first and second oscillators. A counter processes the frequency signals output by the oscillators to generate a digital representation of the current flowing through the voice coil of the VCM.