Anthony D Pei

US Patent:

7974029, Jul 5, 2011

Filed:

Jul 31, 2009

Appl. No.:

12/533950

Inventors:

Chun Sei Tsai - Tustin CA, US
Sang Huynh - Corona CA, US
Anthony L. Pei - Irvine CA, US
Don Brunnett - Pleasanton CA, US
Jahangir John Kasraee - Irvine CA, US
Kent W. Gibbons - Trabuco Canyon CA, US

Assignee:

Western Digital Technologies, Inc. - Irvine CA

International Classification:

G11B 27/36

US Classification:

360 31, 360 48, 360 53, 360 62

Abstract:

A disk drive is disclosed comprising a disk comprising a plurality of tracks, and a head actuated over the disk. A plurality of refresh zones are defined, wherein each refresh zone corresponds to a plurality of the tracks. Data is written to a first refresh zone, and a first zone counter is updated for a second refresh zone at a first rate. Data is written to a third refresh zone, and the first zone counter is updated for the second refresh zone at a second rate different than the first rate.

US Patent:

7929234, Apr 19, 2011

Filed:

Mar 27, 2009

Appl. No.:

12/413408

Inventors:

William B. Boyle - Lake Forest CA, US
Chun Sei Tsai - Tustin CA, US
Anthony L. Pei - Irvine CA, US

Assignee:

Western Digital Technologies, Inc. - Irvine CA

International Classification:

G11B 27/36

US Classification:

360 31, 360 53

Abstract:

A disk drive is disclosed comprising a head actuated over a disk, the disk having a plurality of data tracks, wherein a first plurality of data tracks comprises a first plurality of defect scanned data sectors and a second plurality of data tracks comprises a second plurality of unscanned data sectors. The second plurality of data tracks is divided into a plurality of defect zones. A first number of write commands are received from a host to write data to a first defect zone. A first data sector in the first defect zone is defect scanned in response to the first number of write commands to the first defect zone.