logo

For the Inventor, By the Inventor

The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Patent No.:

US 5515431 B1

PDFFull Text
Date of Patent:
May. 07, 1996

Filed:

Aug. 15, 1994

Speakerphone device with auxiliary circuit for eliminating clicking at

Applicant:
Inventors:

Joachim Kuhnle, Erlenbach, DE;

Wolfgang Roper, Wolpertshausen, DE;

Jurgen Schnabel, Leingarten, DE;

Assignee:

TEMIC TELEFUNKEN microelectronic GmbH, Heilbronn, DE;

Attorney:

Spencer & Frank

Primary Examiner:

Jeffery Hofsass

Assistant Examiner:

Scott L Weaver

Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379388 ; 379395 ; 379421 ;
Abstract

A speakerphone for a telephone circuit includes an output stage that comprises a loudspeaker amplifier coupled to a loudspeaker through a coupling capacitor. An auxiliary circuit includes a reference input element that provides first and second reference voltages which are used to charge the coupling capacitor to a given level prior to the input signal being coupled to the loudspeaker through the coupling capacitor to insure a click-free switch-on of the loudspeaker.

Find Patent Forward Citations

Quick Actions:

Kuhnle, Joachim. (1996). Speakerphone device with auxiliary circuit for eliminating clicking at (U.S. Patent No. 5515431). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5515431

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Loading…