Disk-rotation control apparatus
US6118742A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1998 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Apr 13, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/247
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
If a determination is made that a signal is not normally detected by the pre-pit-region detection circuit 53, an error signal is obtained from a pulse generator 58 to control the rotations of the disk 50. If a determination is made that a signal is normally detected by the pre-pit-region detection circuit 53 and if the synchronizing signals are not normally detected at predetermined intervals, an error signal is obtained from the wobble signal so that the rotations of the disk 50 are controlled. If a determination is made that synchronizing signals are detected by the pre-pit-region detection circuit 53 at predetermined intervals, an error signal is obtained from clocks synchronized with the reproduced signal generated by the PLL circuit 54 so that rotations of the disk 50 are controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.