Write clock phase tracking for magnetic recording device
US8508878B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 2010 |
| Grant date | Aug 13, 2013 |
| Priority date | — |
| Expiry date | Oct 29, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0026
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present disclosure includes systems and techniques relating to control of magnetic recording devices, such as disk drives. A described technique includes receiving a waveform produced by a read head operated with respect to a recording medium and a servo clock signal. A medium can include magnetic data bit cells, a first servo wedge, a second servo wedge, and phase tracking fields, where at least a portion of the phase tracking fields are arranged between the first servo wedge and the second servo wedge. The servo wedges can include respective servo sync marks. The technique includes producing, based on the waveform, a servo detect pulse that indicates a detection of a servo sync mark. The technique includes controlling a first adjustment of a phase of a write clock signal, the first adjustment being responsive to the servo detect pulse. The technique includes producing, based on the write clock signal, samples of the waveform that correspond to phase tracking fields. The technique includes controlling second adjustments of the phase based on the samples to align the write clock signal with at least a portion of the bit cells, the second adjustments being responsive to the phas…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.