Magnetic disk drive with control of sense current of magnetic head
US7636212B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2005 |
| Grant date | Dec 22, 2009 |
| Priority date | — |
| Expiry date | Mar 27, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0018
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An output of a magnetic head changes depending on the environmental temperature of a magnetic disk. In particular, under cold temperature conditions, an output of the head largely decreases mainly due to an increase in coercivity of a magnetic recording medium, which degrades an error rate. In one embodiment of the invention, sense-current optimization processing of a magnetic disk drive comprises the steps of: measuring the environmental temperature; and after a sense-current value which is set from the viewpoint of the reliability of the magnetic head is defined as an upper limit, finding out a sense current Is that can achieve the best error rate (BER) at the temperature. While changing a value of the sense current Is inside the magnetic disk drive, an error rate is measured. Then, a sense current Is_opt at which the best error rate properties are achieved is selected as a new set value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.