Method and apparatus for calibrating a phase locked loop in open-loop
US7375595B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2006 |
| Grant date | May 20, 2008 |
| Priority date | — |
| Expiry date | Nov 4, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/18
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus for calibrating a transitional loop, such as a phase locked loop, are disclosed. An example method includes performing an open loop calibration of a voltage controlled oscillator (VCO). The open loop calibration includes tuning the output oscillation frequency of the VCO to within a predetermined range of frequencies. The example method further includes determining a voltage offset and a gain error of an analog to digital converter (ADC) coupled with the phase locked loop. The example method also includes determining a gain offset of the open loop calibrated VCO using the voltage offset and the gain error of the ADC. In the example method, a signal provided by a charge pump of the PLL is adjusted based on the determined gain offset.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.