Method and apparatus for providing a start-up control voltage
US6407600B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 2000 |
| Grant date | Jun 18, 2002 |
| Priority date | — |
| Expiry date | Jun 27, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/18
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A startup control voltage preset method and apparatus to reduce phase locked loop lock acquisition time at startup. In one embodiment, the disclosed apparatus includes a phase locked loop circuit including a startup circuit that is activated at startup. The startup circuit is coupled to force a control input of a voltage control oscillator of the phase lock loop circuit across a loop filter to a voltage at or near a target nominal operating voltage. In one embodiment, the target nominal operating voltage corresponds to a target operating frequency of the phase locked loop circuit. In one embodiment, the startup circuit is coupled to be activated for a predetermined time at startup. In one embodiment, the startup circuit is coupled to be activated at startup until the control input voltage of the voltage controlled oscillator is at or near a reference voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.