Disk drive detecting head touchdown by applying DC+AC control signal to fly height actuator

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United States of America Patent

PATENT NO 8970978
SERIAL NO

13657016

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Abstract

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A disk drive is disclosed comprising a head actuated over a disk, and a dynamic fly height (DFH) actuator operable to control a fly height of the head over the disk. A DFH control signal is applied to the DFH actuator to decrease the fly height of the head, wherein the DFH control signal comprises a DC component and an AC component comprising an excitation frequency. A touchdown metric is measured over an interval, and the head contacting the disk is detected in response to a frequency component of the touchdown metric at the excitation frequency.

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Patent Owner(s)

  • WESTERN DIGITAL TECHNOLOGIES, INC.

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Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Kermiche, Noureddine Dana Point, US 16 591
Knigge, Bernhard E San Jose, US 47 1064
Shepherd, Stanley H Morgan Hill, US 15 539

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