Some designs and a characterisation method for GaAs operational amplifiers for switched-capacitor applications

Author

Toumazou, Christofer ; Haigh, D.G.

Author_Institution

Dept. of Electr. Eng., Imperial Coll., London

Volume

24

Issue

18

fYear

1988

fDate

9/1/1988 12:00:00 AM

Firstpage

1170

Lastpage

1172

Abstract

A differential to single-ended convertor stage suitable for N -channel depletion-mode GaAs MESFET implementation is modified to allow increased gain. This enhanced input stage is combined with two different high-gain stages to yield two operational amplifier designs suitable for switched capacitor applications. A new procedure for characterising amplifiers in terms of settling time is presented and applied to the above designs. It reveals the ultimate speed limitation for a given amplifier design and allows the MESFET gate widths to be scaled to obtain optimum settling behaviour for any given capacitative load

Keywords

III-V semiconductors; Schottky gate field effect transistors; field effect integrated circuits; gallium arsenide; integrated circuit technology; operational amplifiers; switched capacitor networks; GaAs; MESFET gate widths; N-channel depletion-mode GaAs MESFET; capacitative load; cascodes; characterisation method; differential to single-ended convertor stage; enhanced input stage; high-gain stages; operational amplifier designs; procedure for characterising amplifiers; semiconductors; settling time; switched capacitor applications; ultimate speed limitation;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

Filename

19613