Patent · US Expired

Servo writing a disk drive by synchronizing a servo write clock to a reference pattern on the disk and compensating for repeatable phase error

US7333280B1 · kind B1 · utility

149Cited by
70References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 3, 2004
Grant dateFeb 19, 2008
Priority date
Expiry dateMar 31, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/59666
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of writing product servo sectors on a disk of a disk drive is disclosed. The disk comprises a reference pattern having a plurality of sync marks written around the disk. The sync marks are detected to generate a sync mark detect signal, and a timing recovery measurement is generated in response to the sync mark detect signal. A frequency control signal is generated in response to the timing recovery measurement, and a servo write clock is generated in response to the frequency control signal. A feed-forward compensation value is generated in response to the timing recovery measurement and the frequency control signal, and the timing recovery measurement is adjusted in response to the feed-forward compensation value to compensate for a repeatable phase error in the timing recovery measurement. The servo write clock and the head internal to the disk drive are used to write the product servo sectors to the disk.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.