Automatic frequency calibration apparatus and method for a phase-locked loop based frequency synthesizer
US7982552B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 2009 |
| Grant date | Jul 19, 2011 |
| Priority date | — |
| Expiry date | Sep 12, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/1976
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An automatic frequency calibration apparatus and a method thereof for a phase-locked loop based frequency synthesizer are disclosed. The apparatus includes a frequency-to-digital converter configured to convert a frequency of a VCO output signal to a first digital value, a target value setting section configured to provide a second digital value corresponding to a target frequency, and a finite state machine configured to calibrate the frequency of the VCO output signal by using the difference of the first digital value and the second digital value. Accordingly, the calibration speed and a frequency resolution of the automatic frequency calibration apparatus in a frequency synthesizer may be enhanced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.