Overshoot control for a hard disk drive write head
US6549353B1 · kind B1 · utility
11Cited by
4References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 30, 1999 |
| Grant date | Apr 15, 2003 |
| Priority date | — |
| Expiry date | Dec 30, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0013
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved write drive circuit which includes a discharge circuit added to the base of the bottom transistors of the H-bridge to prevent excessive overshoot and ringing while allowing for higher data rates. The discharge circuit is turned on after the head voltage or current reaches an overshoot condition. In preferred embodiments, the discharge circuit includes variable discharge capability by selecting one or more parallel drive transistors or varying a variable delay in the discharge circuit or any combination of both variables. Both can be controlled by a word written to the disk drive pre-amp over the serial control port.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.