Write clock phase tracking for magnetic recording device
US9013819B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2014 |
| Grant date | Apr 21, 2015 |
| Priority date | — |
| Expiry date | Jun 23, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0026
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Systems and techniques relating to control of magnetic recording devices are described. Such devices can contain a recording medium including magnetic data positions, servo sync marks (SSMs), and phase tracking fields (PTFs) arranged between first and second SSMs. A described technique includes producing, based on a read head's waveform from the recoding medium, a servo detect pulse indicating a SSM detection; producing, based on the waveform, a servo detect pulse that indicates a SSM detection; producing, responsive to the servo detect pulse, calibration pulses, each of the calibration pulses corresponding to a read head's passage over one of the PTFs; and controlling, responsive to the calibration pulses, adjustments of a phase of a write clock signal to align the write clock signal with at least a portion of the data positions, the adjustments being based on groups of samples of the waveform that respectively correspond to the PTFs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.