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, 2001
Filed:
May. 03, 2000
Hitoshi Tomiyama, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An amplifier for amplifying a high frequency signal includes comprises cascade-connected an input npn transistor and an output npn transistor and a bias circuit to control a base current Ib of the input transistor in order to make a DC component of a collector current Ic of the cascade-connected npn transistors constant. A shunt transistor is further connected between a base electrode of the input npn transistor and one terminal of a power source and is connected so that the base current of the input npn transistor flows through a resistor connected between a base electrode and an emitter electrode of the shunt transistor. By lowering a base voltage of the output npn transistor in response to a gain control signal, the collector current Ic is reduced, and a gain of the amplifier is reduced, and simultaneously the shunt transistor is made in shunting operation.