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 8525589 B1

PDF
Full Text
Expired
Date of Patent:
Sep. 03, 2013

Filed:

Jun. 03, 2010
Applicant:

Masayuki Doi, Osaka, JP;

Inventor:

Masayuki Doi, Osaka, JP;

Assignee:

Ricoh Company, Ltd., Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03F 1/14 (2006.01);
U.S. Cl.
CPC ...
Abstract

A disclosed pop sound reduction circuit reducing generation of pop sound at activation or deactivation of an audio amplifier includes a reference voltage circuit generating a reference voltage, a differential amplifier circuit having first and second inputs to amplify the audio signal based on a comparison between the first and second inputs, a triangular voltage generator circuit generating a triangular voltage, a voltage current convertor circuit generating a current proportional to the triangular voltage, a capacitor charged with the generated current to generate a voltage corresponding to the generated current, a constant voltage circuit generating a constant voltage, and a control circuit switching the triangular voltage into the constant voltage to be applied to the voltage current convertor circuit so as to increase the generated voltage if the voltage generated by the capacitor is below the reference voltage when the triangular voltage is equal to or below a predetermined voltage.


Find Patent Forward Citations

Doi, Masayuki. (2013). Pop sound reduction circuit and audio circuit having such pop reduction circuit for use in audio amplifier (U.S. Patent No. 8525589). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/8525589

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

Loading…