Method and apparatus for detecting head flying height in a disk drive
US5909330A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 1996 |
| Grant date | Jun 1, 1999 |
| Priority date | — |
| Expiry date | Dec 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/6029
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a system for determining whether the flying height of a read/write head above a disk in a disk drive is within an acceptable range, in substantially real time. The system relies on variations in read signal resolution with flying height to make the determination. In one embodiment, read signal resolution is measured and compared to a predetermined threshold value to determine whether the present flying height is in the desired range. In another embodiment, the number of peaks in a read signal that are detected (and/or not detected) by a detector is used to determine whether the head is in the proper flying height range. Because of read signal resolution effects, the number of detected peaks will decrease as the flying height of the head is increased. The system also provides for postponing a transfer of data to/from the disk when it is determined that the head is not within the acceptable range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.