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.:
Date of Patent:
May. 11, 2004
Filed:
Nov. 19, 2002
Applicant:
Inventors:
Toshihiko Masuda, Tokyo, JP;
Kazunobu Ohkuri, Kanagawa, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03F 3/38 ; H03F 3/217 ;
U.S. Cl.
CPC ...
H03F 3/38 ; H03F 3/217 ;
Abstract
A power amplifier circuit includes a pair of PWM circuits, to which an input signal is supplied, a pair of push-pull circuits, and drive circuits for supplying the outputs of the PWM circuits to the push-pull circuits as drive signals. A speaker is arranged between the output end of one push-pull circuit and the output end of the other push-pull circuit. The drive circuits alternately drive the respective push-pull circuits every cycle time of a PWM signal. The circuit can suppress radiation caused by the variation in output voltages.