Patent · US Expired

Multimode frequency synthesizer having high loop gain in frequency seek mode

US5861766A · kind A · utility

29Cited by
12References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 1997
Grant dateJan 19, 1999
Priority date
Expiry dateApr 17, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2020/1282
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A frequency synthesizer has multiple modes of operation including a relatively short-duration frequency seek mode and a relatively long-duration normal mode. The synthesizer responds to a reference frequency signal and produces a periodic signal at a frequency that is a rational number times the frequency of the reference frequency signal. The synthesizer comprises a VCO, a feedforward state machine, a feedback state machine, a phase comparator, controllable gain circuitry between the phase comparator and the VCO, and logic circuitry that coordinates the operation of the feedforward and feedback state machines during the seek mode.

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