Patent · US Expired

Programmable digital filter for stable interval detection

US5848237A · kind A · utility

9Cited by
5References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 15, 1996
Grant dateDec 8, 1998
Priority date
Expiry dateMay 15, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H17/0294
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A programmable digital filter. The digital filter detects a predefined pattern over a programmably variable duration. The filter includes an interval register which is coupled to receive an interval count. A sample register is coupled to receive a plurality of samples of an input signal which is sampled at an interval determined by the interval count. A plurality of pattern matching circuits generate a pattern match output if the plurality of samples matches one of a plurality of predetermined patterns, and a state logic circuit generates a signal if a new match is found. The pattern matching circuits may be stable high and stable low test circuits which cooperate to determine if all of the plurality of samples are of a consistent logic value.

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