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:
Nov. 09, 1999
Filed:
Jan. 20, 1998
Osamu Ishikawa, Kyoto, JP;
Takahiro Yokoyama, Hyogo, JP;
Taketo Kunihisa, Osaka, JP;
Junji Ito, Osaka, JP;
Masaaki Nishijima, Osaka, JP;
Shinji Yamamoto, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A high-frequency power amplifier comprises a transistor for high-frequency power which operates and whose current-voltage characteristics greatly change when positive voltage is supplied on its input terminal, an input bias circuit, an output bias circuit, an input impedance matching circuit, an output impedance matching circuit, and a positive voltage generation circuit. The positive voltage generation circuit comprises a detection circuit which detects part of the high-frequency power which is entered to or outputted from the transistor for high-frequency power, a rectification circuit which rectifies the part of the high-frequency power outputted from the detection circuit and outputs pulsating positive voltage, and a smoothing circuit which smoothes the pulsating positive voltage outputted from the rectification circuit and outputs positive voltage. The positive voltage generation circuit outputs positive voltage which increases or decreases in accordance with an increase or decrease in the detected part of the high-frequency power to the input terminal of the input bias circuit, without intervention of a direct-current power supply.