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. 28, 2012
Filed:
Sep. 22, 2011
Katsumasa Hijikata, Osaka, JP;
Mineyuki Iwaida, Kyoto, JP;
Katsumasa Hijikata, Osaka, JP;
Mineyuki Iwaida, Kyoto, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A variable gain amplifier includes a direct current (DC) blocking capacitor which receives an input signal at a first terminal, a variable amplifier unit, having a variable transistor size, which amplifies an output of a second terminal of the DC blocking capacitor, a load impedance unit coupled to an output of the variable amplifier unit, a bias resistor having a first terminal coupled to the second terminal of the DC blocking capacitor, a variable bias voltage generator which applies a variable bias voltage to a second terminal of the bias resistor, and a gain controller which provides control to decrease the variable bias voltage when an effective transistor size of the variable amplifier unit is controlled so as to increase, and provides control to increase the variable bias voltage when the effective transistor size of the variable amplifier unit control is controlled so as to decrease.