Donald D Turner

US Patent:

6462896, Oct 8, 2002

Filed:

Nov 30, 2000

Appl. No.:

09/728627

Inventors:

Raffi Codilian - Irvine CA
Donald R. Turner - Laguna Hills CA

Assignee:

Western Digital Technologies, Inc. - Lake Forest CA

International Classification:

G11B 509

US Classification:

360 48, 360 75, 360 60

Abstract:

The present invention may be embodied in a method for minimizing adjacent track data loss due to a shock event occurring during a write operation in a disk drive. The method includes providing a plurality of adjacent concentric data tracks, for storage of user data, that are spaced-apart by a track pitch. The plurality of data tracks are allocated into a first set and a second set such that the data tracks of the first and second sets are interleaved physically with one another. A first series of logical block addresses are assigned to the first set of data tracks such that the first series of logical block addresses are consecutively numbered between successive ones of the first set of data tracks. A second series of logical block addresses, which consecutively follow the first series of logical block addresses, are assigned to the second set of data tracks such that the second series of logical block addresses are consecutively numbered between successive ones of the second set of data tracks. The assignment of logical block addresses to the first and second sets of data tracks results in the disk drive postponing writing to the second set of data tracks, thereby reducing data loss due to a shock event causing adjacent track encroachment occurring prior to writing to the second set of data tracks.

US Patent:

6707635, Mar 16, 2004

Filed:

Oct 5, 2000

Appl. No.:

09/684561

Inventors:

Raffi Codilian - Irvine CA
Donald R. Turner - Laguna Hills CA

Assignee:

Western Digital Technologies, Inc. - Lake Forest CA

International Classification:

G11B 5596

US Classification:

360 7704, 360 7702

Abstract:

The present invention may be embodied in a method, and related apparatus, for determining a repeatable runout (RRO) compensation value sets for a plurality of tracks on a disk in a disk drive, wherein the disk drive is initially manufactured and then shipped for installation in a host system. Each track comprises a plurality of embedded servo sectors that define a circumferential path that may have RRO requiring compensation during track following. The method comprises determining first RRO value sets for a first portion of the tracks to a first desired learning level by measuring the RRO for the first portion tracks based on a first predetermined number of disk rotations during the initial manufacturing of the disk drive. The first portion tracks are not adjacent to each other. Then, after the disk drive is shipped for installation in the host system, RRO value sets are determined for a second portion of tracks to a second desired learning level by measuring the RRO for the second portion tracks based on at least a second predetermined number of disk rotations.