Patent · US Expired

Filter control circuit

US5006733A · kind A · utility

15Cited by
4References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 11, 1990
Grant dateApr 9, 1991
Priority date
Expiry dateMay 11, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H11/1291
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A filter control circuit uses a compound FET as a resistance element. The compound FET includes parallel FETs having different gate widths to provide different drain-source resistance characteristics, which overlap to provide an extended operating region, that approaches a linear curve for the combined resistance characteristic. The control voltage used to control the compound FET may be coupled to like compound FETs in the filter being controlled.

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