Patent · US Expired

Activation circuit for battery-operated security alarm detection system

US5254897A · kind A · utility

6Cited by
6References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 1992
Grant dateOct 19, 1993
Priority date
Expiry dateOct 7, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B13/04
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The present invention relates to an activation circuit for a battery-operated security alarm detection system where current drain and, therefore, battery life is of concern. It employs a non-current drawing piezo element which only sees part of the frequency band of interest to briefly activate or wake up a current-drawing electret microphone which has a bandwidth broad enough to sees the entire audio band of interest.

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