Phase-locked loop control for reading data off storage media
US4901035A · kind A · utility
9Cited by
4References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 20, 1988 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Apr 20, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/089
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An improved phase-locked loop control having a phase detector receptive of a data preamble of all "ones" from a storage sub-system for producing early and late signals to a voltage controlled oscillator in order for the frequency of the oscillator to be synchronized with the frequency of the data. A pattern detector senses the incoming preamble pulses and prevents the generation of the early and late signals when a preamble pulse is not present within a predetermined window of time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.