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:
Dec. 26, 1995
Filed:
Sep. 19, 1994
Rohm Co., Ltd., Kyoto, JP;
Abstract
The present invention includes a first push-pull amplifier for amplifying an audio signal, a second push-pull amplifier for inverting and amplifying the audio signal, a switching circuit for switching power from a power source line at a frequency exceeding an audible frequency and feeding the first or second amplifier, a control circuit for controlling a switching period of the switching circuit such that the feeding power is changed correspondingly to a level of the audio signal correspondingly to a first difference in voltage between one of the audio signal and the audio signal amplified by the amplifier and the power or a second difference in voltage between one of the audio signal and the audio signal amplified by the second amplifier and the feeding power and a capacitor provided between the outputs of the first and second amplifiers, a loud speaker being driven by outputs of the first and second amplifiers.