Patent · US Expired

Gm-C time constant tuning circuit

US7239197B2 · kind B2 · utility

7Cited by
2References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 30, 2005
Grant dateJul 3, 2007
Priority date
Expiry dateNov 30, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03D13/004
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A circuit including a Gm-C filter and an automatic Gm-C time constant tuning circuit is provided. The tuning circuit includes a reference conductor, a reference capacitor coupled to the reference conductor, a comparator generating signals according to a reference signal and the voltage signal at the output of the reference conductor, a feedback capacitor, and a charge pump charging and discharging a feedback capacitor according to the output of the comparator. The feedback capacitor provides a control voltage feedback to the tuning circuit and to the Gm-C filter for adjusting the conductance. Hence, in doing so, errors like manufacturing variation and offset can be prevented.

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