Two CMOS large current-gain cells with linearly variable gain and constant bandwidth

Author

Wang, Zhenhua

Author_Institution

Dept. of Electr. Eng., Swiss Federal Inst. of Technol., Zurich, Switzerland

Volume

39

Issue

12

fYear

1992

fDate

12/1/1992 12:00:00 AM

Firstpage

1021

Lastpage

1024

Abstract

Two CMOS current gain cells with linear open-loop transfer characteristics are proposed: one for differential inputs and the other for single-ended input. Both cells have a large gain variable linearly via a small DC current, a constant bandwidth independent of the gain, and a very low distortion over a large input range. Different implementations are discussed and compared. Computer simulations on the single-ended cell show a gain of 0.75 to 130 with the control current from 4 to 15 μA, a THD of less than 0.5% for input up to 70% of the control current, and a constant bandwidth of 1.4 MHz

Keywords

CMOS integrated circuits; DC amplifiers; differential amplifiers; linear integrated circuits; 1.4 MHz; 4 to 15 muA; CMOS; constant bandwidth; current-gain cells; differential inputs; linear open-loop transfer characteristics; linearly variable gain; low distortion; single-ended input; Bandwidth; Bipolar transistors; Circuits; Computer simulation; Controllability; Gain control; MOSFETs; Mirrors; Transconductance; Voltage;

fLanguage

English

Journal_Title

Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on

Publisher

ieee

ISSN

1057-7122

Type

jour

DOI

10.1109/81.207727

Filename

207727