A linear operational transconductance amplifier for instrumentation applications

Author

Chung, Won-Sup ; Kim, Kwang-Ho ; Cha, Hyung-Woo

Author_Institution

Dept. of Semicond. Eng., Chongju Univ., South Korea

Volume

41

Issue

3

fYear

1992

fDate

6/1/1992 12:00:00 AM

Firstpage

441

Lastpage

443

Abstract

A linear operational transconductance amplifier (OTA) is described that consists of a linear transconductor and a translinear current gain cell followed by three current mirrors. The proposed circuit has superior linearity and temperature characteristic when compared with the commercially available OTA. A prototype circuit with a transconductance of 50 μS has been built with discrete bipolar transistors producing a linearity error of less than ±20% over an input voltage range from -0.8 to 0.8 V. The prototype OTA circuit also exhibits a transconductance that is linearly dependent on a bias current varying over four decades with a sensitivity of 1 S/A

Keywords

instrumentation amplifiers; operational amplifiers; base width modulation; current mirrors; discrete bipolar transistors; linear operational transconductance amplifier; linearity; linearity error; second order effects; temperature characteristic; temperature stability; translinear current gain cell; Bipolar transistors; Circuits; Instruments; Linearity; Mirrors; Operational amplifiers; Prototypes; Temperature; Transconductance; Transconductors;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.153345

Filename

153345