Disc recording and/or reproducing apparatus and its motor drive control circuit
US6088315A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 1998 |
| Grant date | Jul 11, 2000 |
| Priority date | — |
| Expiry date | May 19, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10595
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A motor rotation control circuit of a disc recording and/or reproducing apparatus has first and second rotation control units and a switching circuit. Information extracted from data read out from a disc is supplied to the first rotation control unit. The first rotation control unit forms a first control signal to rotate a disc rotating motor at a constant linear velocity. A signal indicative of the detection of the rotation of the motor to rotate, the disc is supplied to the second rotation control unit. The second rotation control unit forms a second control signal to rotate the motor at a constant angular velocity. The second rotation control unit fetches rotational speed information of the disc when switching from the first rotation control unit to the second rotation control unit and forms the second control signal to control the motor on the basis of the fetched rotational speed information of the disc when switched from the first rotation control unit to the second rotation control unit. The switching circuit switches the first and second control signals on the basis of a switching signal which is supplied from the controller and outputs the switched control signal. The swit…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.