Patent · US Expired

Servo data recovery circuit for disk drive having digital embedded sector servo

US5420730A · kind A · utility

78Cited by
16References
21Claims
0Family size

Inventors

Key dates

Filing dateJan 11, 1994
Grant dateMay 30, 1995
Priority date
Expiry dateJan 11, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2020/1284
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus are provided for recovering servo information in a disk drive for positioning a data transducer head relative to concentric data tracks wherein the head reads user data encoded in a predetermined data code and reads servo information within plural servo sectors embedded in each data track defined on a storage surface of a rotating disk. The data tracks are arranged in plural groups of concentric tracks within concentric zones wherein each zone has a user data transfer rate selected in relation to disk radius, the servo information being recorded in at least three patterns within each embedded servo sector: a servo sync pattern, a user data code violating pattern, and a servo data bit pattern. A servo data recovery circuit implements the method comprising the steps of: PA1 timing expected arrival of a servo sector with a sector timer, PA1 at the expected arrival of the servo sector detecting a said servo sync pattern with a servo sync pattern detector, PA1 detecting at least one said user data code violating pattern with a user data code violating pattern detector, PA1 detecting recurrent servo data bit patterns as binary data bits with a data reader, PA1 dete…

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