Maxtor Corporation

Seagate Technology Incorporated

Western Digital Technologies, Inc.

Lloyd E Levy

Don Brunnett

Thomas O Melrose

Yu Sun

Duc H Banh

James W Hargarten

Stephen H Perlmutter

Adrián Cerdá

Danilo Bueno

Jingbo Yu

Adrian E Cerda

Richard T Curran

Daniel J Gunderson

Bruce C Schardt

Pang L Tan

A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of tracks. Data is read from a target track, and an off-track read capability (OTRC) is generated for a plurality of segments of the target track. For example, an OTRC may be generated for a plurality of data sectors, wherein the combined OTRCs may be evaluated to compute an average track center, or an average track width, or a repeatable runout (RRO).

Disk drive generating off-track read capability for a plurality of track segments

Performing embedded runout correction for a track on a rotational data storage disk includes measuring written-in runout for the track, selecting a number of revolutions in response to the measured written-in runout of the track, calculating embedded correction values for the track for the selected number of revolutions of the rotational data storage disk, and storing the embedded correction values.

Embedded runout correction based on written-in runout measurement

A disk drive measures the radial misposition of tracks and repositions the tracks at regularly spaced intervals. Written in runout (WRO) in servo bursts is determined to calculate track spacing and squeeze among adjacent tracks. Tracks with improper spacing are repositioned by adding a squeeze correction term to the servo wedges. Thereafter, when the disk drive operates to store data, the servo bursts are used to calculate a position error signal (PES), and the squeeze correction term is combined with the PES to position the head at a proper track radius.

Method to correct radial misposition of data tracks using stitched correction fields

A method and apparatus for providing a temporary utility zone in a disk drive. A disk surface has a write head associated therewith. The write head is used to write spiral servo information and a propagation state indicator onto the disk surface. The spiral servo information and propagation state indicator are used to perform a self-servo write operation on the disk surface.

Method and apparatus for performing a spiral self-servo write operation in a disk drive using an auto detection scheme

Method to correct radial misposition of data tracks

A method and apparatus for writing servo information to disks within a disk drive is disclosed. A servo track writer is used to write first servo information to the disks. The disk drive is then sealed, and the read/write heads within the disk drive are used to fill in second servo information. The first servo information includes digital information and A, B, C, and D servo bursts for a first number of tracks on the disks. The first servo information also includes digital information and A and B servo bursts for the remaining tracks on the disks. After the disk drive is sealed in the manufacturing process, the read/write heads within the disk drive fill in the second servo information, which includes C and D servo bursts for the remaining tracks. The read head reads the first servo information in the first number of tracks, and the position of the write head is adjusted based on the first servo information. The write head is then used to write the second servo information to a first remaining track, resulting in complete servo information for the first remaining track. The read head then reads the complete servo information in the first remaining track, and writes the second servo information for a second remaining track. This continues until the complete servo information is propagated to all of the remaining tracks.

Partial servo write fill in

A disk drive test device for performing a test (e.g., power only self test, tests which use a serial interface) on at least one disk drive at a time. The test device includes an electrical connector which is configured so as to be able to provide the necessary electrical interconnections for executing a test on disk drives having different types of drive interface connectors (i.e., the same electrical connector may be used with at least 2 different types of drive interface connectors). There is no need to use an in-line adapter to electrically interconnect a disk drive having a first drive interface connector or to electrically interconnect a disk drive having a second drive interface connector. There is also is no need to change out the electrical connector when performing a test on disk drives which use this different types of drive interface connectors.

Disk drive test rack with universal electrical connector

Growing community of inventors

San Jose, CA, United States of America

Lloyd E Levy