Patent · US Expired

VCO tuning curve compensated charge pump current synthesizer

US6680653B2 · kind B2 · utility

11Cited by
4References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 2000
Grant dateJan 20, 2004
Priority date
Expiry dateDec 20, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/0898
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A system provided for controlling an output frequency of a voltage controlled oscillator relative to a reference frequency. A method includes the steps of detecting a phase error between a divided output of the voltage controlled oscillator and the reference frequency, pumping a frequency control input of the voltage controlled oscillator with the phase error and adjusting a pumping gain based upon a magnitude of the frequency control input to the voltage controlled oscillator.This apparatus includes a phase detector adapted to detect the phase error between the divided output of the voltage controlled oscilator and the reference frequency and a charge pump adapted to pump the frequency control input of the voltage controlled oscillator with the phase error. The apparatus also includes a gain controller adapted to adjust the pumping gain based upon the magnitude of the frequency control input to the voltage controlled oscillator.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.