Patent · US Expired

Self-calibration of a PLL with multiphase clocks

US7298809B2 · kind B2 · utility

4Cited by
1References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 20, 2003
Grant dateNov 20, 2007
Priority date
Expiry dateOct 17, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/18
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A Phase-Locked Loop with multiphase clocks is provided. The Phase-Locked Loop includes a main loop, a calibration loop, and a Demultiplexer. The main loop includes, coupled in series, a Phase Frequency Detector, a Main Charge Pump, a Main Loop Filter, a Multi-Phase Voltage Controlled Oscillator and a Phase-switching Fractional Divider. The calibration loop includes Y Calibration Loop Filters, with Y being an integer, coupled to the Multi-Phase Voltage Controlled Oscillator, and Control Logic for controlling the Phase-Switching Fractional Divider. The Demultiplexer is coupled between an output of the Main Charge Pump and inputs of the Main Loop Filter and the Y Calibration Loop Filters. A Reference Frequency Signal is coupled to the Phase Frequency Detector, a control signal from the Control Logic is coupled to the Demultiplexer, and a Calibration Signal is coupled to a control input of the Control Logic.

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