Patent · US Expired

Phase detector

US5781036A · kind A · utility

3Cited by
4References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 1997
Grant dateJul 14, 1998
Priority date
Expiry dateApr 1, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03D13/00
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A phase detector biased in a manner to alleviate the mismatch between the biasing current sources and the phase detector core bias currents. The bias setting resistors are coupled together at a common node that forms the negative input of a differential feedback amplifier. The positive input to the amplifier is referenced to a reference voltage, and the output of the amplifier controls the biasing current sources. The feedback amplifier forces the average voltage at the current source outputs to approximately match the reference voltage applied to its positive input. Thus the average bias current from the bias current sources is forced to track the average bias currents of the phase detector core.

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