Servo apparatus with offset compensation
US4924454A · kind A · utility
2Cited by
2References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 27, 1988 |
| Grant date | May 8, 1990 |
| Priority date | — |
| Expiry date | Sep 27, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0908
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A servo loop arrangement for the reproduction of data from a record medium has interleaved pulse trains of opposite polarity pulses applied to it to add to the servo loop control signal which undesirably includes an offset voltage. The resultant increasing opposite polarity changes in the control signal in successive pulse train intervals are threshold detected. The numbers of opposite polarity pulses required to reach the threshold values are compared and any difference in number is converted to a compensation signal which is added to the servo loop to compensate for the offset voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.