Disk drive detecting different asperities on a disk using different sensor bias settings

US8902533B1 · kind B1 · utility

Assignee

• Western Digital Technologies, Inc. · US

Inventors

• Carl E. Barlow · Lake Forest, US
• Chun Sei Tsai · Tustin, US
• Chirag C. Patel · Rancho Santa Margarita, US
• Boon Sien Chew · Klang, MY
• Thomas A. O'Dell · Campbell, US
• David Wachenschwanz · Saratoga, US
• David E. Fowler · Gainesville, US

Key dates

• Filing date: Aug 30, 2013
• Grant date: Dec 2, 2014
• Expiry date: Aug 30, 2033

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B5/40
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A disk drive is disclosed comprising a disk comprising a plurality of data tracks, and a head actuated over the disk, the head comprising an asperity sensor operable to generate a sensor signal having a magnitude based on a bias setting of the asperity sensor. The asperity sensor is configured with a first bias setting and a first asperity on the disk is detected based on the sensor signal generated at the first bias setting. The asperity sensor is configured with a second bias setting different from the first bias setting and a second asperity on the disk is detected based on the sensor signal generated at the second bias setting.