Sampled amplitude read channel employing a user data frequency synthesizer and a servo data frequency synthesizer
US5796535A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 1995 |
| Grant date | Aug 18, 1998 |
| Priority date | — |
| Expiry date | May 12, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1258
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A sampled amplitude read channel incorporated within a magnetic disk storage system for reading data recorded in concentric tracks on a magnetic medium, where the data comprises user data sectors recorded at varying data rates across a plurality of predefined zones and embedded servo data sectors recorded at the same data rate across the zones. The sampled amplitude read channel comprises a timing recovery component for synchronous sampling of a read signal from a magnetic read head positioned over the magnetic medium, a gain control component for adjusting the amplitude of the read signal, and a DC offset component for cancelling a DC offset in the read signal. These components are dynamically configured to operate according to whether the read channel is processing user data or embedded servo data. A user data frequency synthesizer and a servo data frequency synthesizer lock the timing recovery component to a reference frequency and provide a coarse center frequency control signal corresponding to the user data or servo data mode. The read channel further employs pipelined reads to reduce the physical gap between sectors on the medium. In addition, an improved sync mark detector …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.