Control apparatus for a recording medium drive motor in a digital information reproducing apparatus
US4423498A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1981 |
| Grant date | Dec 27, 1983 |
| Priority date | — |
| Expiry date | Oct 13, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/916
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A digital audio disc (DAD) reproducing apparatus comprises pulse width detection and pulse width-to-voltage conversion means for detecting a signal having a predetermined pulse width such as a maximum or minimum pulse width of code modulated digital data signals reproduced by a pickup and converting the detected signal to a voltage proportional to the pulse width, and pulse width error detection means for detecting an error between the converted voltage and a reference voltage corresponding to a reference pulse width. Since the pulse width of the digital data signal changes with a clock rate, the error from the reference voltage represents an error in the clock rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.