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:
Aug. 19, 2003
Filed:
Apr. 17, 2002
Kazuharu Aoki, Fukushima-ken, JP;
Jiro Kikuchi, Fukushima-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
A transmission signal which is output from a power amplifier is rectified by a first rectifying circuit and is then input to a first transistor of a voltage-to-current converting circuit, while the reference voltage is output from a second rectifying circuit and is then input to a second transistor of the voltage-to-current converting circuit. The output current of the first transistor is subtracted from the output current of the second transistor via a first current-mirror circuit, and a current that is proportional to the output voltage of the power amplifier is caused to flow to a two-terminal p-n junction electronic device. Then, a voltage that is proportional to the logarithm of the current is output from across the p-n junction electronic device.