Step gain amplifier with impedance unchanged in gain control

Author

Tanabe, M. ; Fukuda, T. ; Nishii, K.

Author_Institution

Corporate Manuf. & Dev. Div., Matsushita Electr. Ind. Co. Ltd., Osaka, Japan

fYear

2002

fDate

3-4 June 2002

Firstpage

209

Lastpage

212

Abstract

A novel gain control method without impedance alternation in a gain control action has been developed. The method was based on the traditional current switch gain control scheme. A low gain mode has not only a DC feed-through as in the conventional method but also an RF feed-through with an RC network and a common-base transistor. An implemented differential Low Noise Amplifier exhibited the complete suppression of the impedance alternation effect. The details of the circuit topology are presented in this paper.

Keywords

RC circuits; UHF amplifiers; UHF integrated circuits; automatic gain control; cellular radio; differential amplifiers; network topology; DC feedthrough; RC network; RF feedthrough; circuit topology; common-base transistor; current switch scheme; differential low noise amplifier; gain control; gain mode; step gain amplifier; Circuit noise; Dynamic range; Gain control; Impedance; Low-noise amplifiers; Radio frequency; Radiofrequency amplifiers; Semiconductor device noise; Switches; Transconductance;

fLanguage

English

Publisher

ieee

Conference_Titel

Radio Frequency Integrated Circuits (RFIC) Symposium, 2002 IEEE

Conference_Location

Seattle, WA, USA

ISSN

1529-2517

Print_ISBN

0-7803-7246-8

Type

conf

DOI

10.1109/RFIC.2002.1012033

Filename

1012033