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:
Sep. 12, 1995
Filed:
Feb. 22, 1994
Applicant:
Inventors:
Kei Nishioka, Kyoto, JP;
Masanori Fujisawa, Kyoto, JP;
Assignee:
Rohm Co., Ltd., Kyoto, JP;
Primary Examiner:
Int. Cl.
CPC ...
H03F / ; H03F / ;
U.S. Cl.
CPC ...
330273 ; 330295 ; 330297 ;
Abstract
The present invention includes an amplifier for amplifying an audio signal, a switching circuit for switching power from a power source line at a frequency exceeding an audible frequency and feeding the amplifier and a control circuit for controlling a switching period of the switching circuit such that the power feeding the amplifier correspondingly to a difference in voltage between the feeding power and one of the voltage of the audio signal and the voltage of the audio signal amplified by the amplifier is changed correspondingly to a level of the audio signal.