05384524 is referenced by 27 patents and cites 40 patents.

A voice coil motor ("VCM") control circuit controls operation of a VCM which positions a disk drive head/actuator arm assembly. A data processor is continuously updated with the current position and relative radial velocity of the disk drive head/actuator arm assembly. The data processor provides signals to a digital-to-analog converter ("DAC") of the VCM control circuit representative of the amount of energy necessary to move the head/actuator arm assembly to a parking position from a current position. The DAC generates an analog signal which is applied to a capacitor. When an undervoltage condition occurs, the signal stored in the capacitor is applied to amplifier circuitry to be used as an initial condition reference signal from which signals are generated to park the head/actuator arm assembly in a desired parking position.

Title
Voice coil motor control circuit and method for servo system control in a computer mass storage device
Application Number
8/115237
Publication Number
5384524
Application Date
September 2, 1993
Publication Date
January 24, 1995
Inventor
Paul M Romano
Boulder
CO, US
Agent
William J Kubida
Assignee
Cirrus Logic
CA, US
IPC
G05B 19/18
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