Phase locked loop circuit having temperature compensated VCO control voltage
US4717891A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1986 |
| Grant date | Jan 5, 1988 |
| Priority date | — |
| Expiry date | Jun 20, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L1/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A phase locked loop circuit including a controllable oscillator, a phase detector for detecting a phase difference between an output signal of the oscillator and an input signal, and a control signal generator for generating a control signal for controlling an oscillation frequency of the oscillator on the basis of the output of the phase detector. The phase locked loop circuit also includes a feedback circuit for controlling a level of the control signal on the basis of a DC level thereof. The feedback circuit is able to temperature compensate for changes in the oscillator output signal thereby keeping the lock range of the phase locked loop circuit constant against variations in temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.