A Wideband CMOS Variable Gain Amplifier With an Exponential Gain Control

Author

Lee, Hui Dong ; Lee, Kyung Ai ; Hong, Songcheol

Volume

55

Issue

6

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

1363

Lastpage

1373

Abstract

A CMOS wideband cascaded variable gain amplifier (VGA) with a temperature-independent exponential gain control characteristic is presented in this paper. The exponential gain control function is realized using parasitic bipolar transistors and a control signal converter. The bandwidth is extended using an inductive peaking technique for high-frequency operations. The gain of the VGA varies from -38.8 to 55.3 dB in relation to the control voltage that varies from 0 to 1.8 V. The bandwidth of the proposed VGA is approximately 900 MHz with a gain control range of 94.1 dB. The proposed VGA includes a dc offset cancellation loop to avoid amplification of the dc offset. The VGA is powered by 1.8 V with 11.4 mA. The VGA chip including bondpads occupies an area of 850 mum times 490 mum.

Keywords

CMOS integrated circuits; bipolar analogue integrated circuits; wideband amplifiers; control signal converter; control voltage; current 11.4 mA; gain 55.3 dB; gain 94.1 dB; inductive peaking technique; parasitic bipolar transistors; size 490 mum; size 850 mum; temperature-independent exponential gain control; voltage 0 V to 1.8 V; wideband CMOS variable gain amplifier; Bandwidth; Bipolar transistors; Broadband amplifiers; CMOS technology; Digital control; Dynamic range; Gain control; Multiaccess communication; Power control; Voltage control; CMOS analog integrated circuit; gain control; linear-in-decibel gain characteristic; temperature compensation; variable gain amplifier (VGA); wideband systems;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2007.896787

Filename

4230874