Patent · US Expired

On-chip self-tuning filter system

US5281931A · kind A · utility

36Cited by
7References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 8, 1992
Grant dateJan 25, 1994
Priority date
Expiry dateOct 8, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H11/04
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An on-chip apparatus and method are provided for automatically tuning a continuous time filter in which a single filter selectively filters an information signal or, when tuning is desired, an unfiltered reference signal. During tuning, a controller determines the amplitudes of the unfiltered and filtered reference signals and their ratio. From the ratio, the controller ascertains a corresponding center or tuned frequency of the filter. If the ascertained frequency does not substantially equal a desired tuned frequency, the controller directs a bias controller to adjust the bias of the filter until the tuned frequency is substantially equal to the desired tuned frequency.

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