Fly on demand in situ clearance measurement concept in hard disk drive
US7317590B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 2006 |
| Grant date | Jan 8, 2008 |
| Priority date | — |
| Expiry date | Feb 28, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for determining a flying height of a head of a hard disk drive. The disk drive includes a pre-amplifier and an automatic gain control (“AGC”) circuit that are connected to the head. The method includes determining a first automatic gain control value based on AGC values at two delta pre-amplifier gain settings. A second automatic gain control value is determined based on AGC values at two different flying heights. A difference between the flying heights can be determined from the first and second automatic gain control values. If one of the flying heights is set to 0 the difference in gain values is equal to the flying height of the head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.