Patent · US Expired

Frequency selection circuit for hearing aids

US4790018A · kind A · utility

18Cited by
18References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 11, 1987
Grant dateDec 6, 1988
Priority date
Expiry dateFeb 11, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R25/502
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A signal processing circuit for hearing aids includes a broadband peak detector for generating a control voltage based upon the sound pressure level of an incoming acoustical signal over its entire frequency spectrum. The control signal is used to determine the cut-off frequency of a voltage controlled adaptive high-pass filter. An amplified electrical signal, corresponding to the acoustical signal, also is provided to the high-pass filter. In setting the cut-off frequency, the control voltage causes the high-pass filter to selectively suppress the low frequency portion of the signal, generating a modified signal in which the noise component is reduced.

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