Patent · US Expired

PRML sampled data channel synchronous servo detector

US5384671A · kind A · utility

297Cited by
11References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 23, 1993
Grant dateJan 24, 1995
Priority date
Expiry dateDec 23, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2220/20
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A synchronous servo data detection subsystem for a PRML sampled data channel of a hard disk drive including a plurality of radially extending servo sectors embedded on a rotating data storage surface. Each servo sector includes a servo synchronization field, a synchronous servo address mark field, and fields providing coarse and fine head position information. A data head reads and writes data signals from and to the storage surface, and a voice coil actuator structure positions the head at each selected data track under control of a head position servo loop. The sampled data channel receives, synchronously samples and decodes analog signals into digital data. and reads the servo fields as the data head passes over each servo sector. The servo detection system includes a timing loop for synchronizing the sampled data channel to the servo synchronization field to provide synchronous samples from the servo sector, a synchronous servo address mark pattern detector connected to an output of the sampled data channel for detecting the unique recording pattern and for thereupon generating a servo address mark found signal, a synchronous coarse head position information detector connected …

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