Disk drive employing seek time vcm ir voltage calibration for velocity control of an actuator arm
US6795268B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 31, 2000 |
| Grant date | Sep 21, 2004 |
| Priority date | — |
| Expiry date | Jun 24, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59605
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A disk drive is disclosed comprising a disk, a head, an actuator arm for actuating the head radially over the disk during a seek operation, and a voice coil motor (VCM) for rotating the actuator arm about a pivot, the VCM comprising a coil comprising a VCM resistance R. A back EMF voltage detector measures a back EMF voltage across the coil, and a current detector detects a current I flowing through the coil. An IR voltage detector, responsive to the current I detected by the current detector, detects an IR voltage proportional to the current I times the VCM resistance R. A voltage compensator substantially cancels the IR voltage from the measured back EMF voltage to generate a compensated back EMF voltage. A control voltage generator, responsive the compensated back EMF voltage, generates a control voltage applied to the coil to generate the current I flowing through the coil. A memory stores a first compensated back EMF voltage generated at a first time period of the seek operation. A comparator compares the first compensated back EMF voltage stored in the memory to a second compensated back EMF voltage generated at a second time period of the seek operation. A calibrator, respon…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.