Apparatus and method for reducing thermal interference in MR heads in disk drives
US6473251B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 1999 |
| Grant date | Oct 29, 2002 |
| Priority date | — |
| Expiry date | Sep 17, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus (and method) is provided that reduces thermal interference in the read signal of a disk drive. A variable or programmable resistance is used to change the transfer function of a filter in the read channel of the disk drive to filter the read signal. The filter has a first transfer function (first cut-off frequency) related to the programmed resistance during normal operation of the disk drive (i.e. when thermal interference is not detected). When thermal interference is detected in the read signal, the resistance is programmed to another value resulting in the filter having a second transfer function (second cut-off frequency). The resistance element includes a transconductance amplifier whose transconductance is variable or programmable to different values resulting in different programmable transfer functions (or one of a multitude of cut-off frequencies) for the filter. In the preferred embodiment, detection of thermal interference increases the cut-off frequency of the filter thereby filtering, or reducing the effects of, the thermal interference in the read signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.