Circuit techniques for reducing the effects of op-amp imperfections: autozeroing, correlated double sampling, and chopper stabilization

Author

Enz, Christian C. ; Temes, Gabor C.

Author_Institution

Electron. Lab., Swiss Federal Inst. of Technol., Lausanne, Switzerland

Volume

84

Issue

11

fYear

1996

fDate

11/1/1996 12:00:00 AM

Firstpage

1584

Lastpage

1614

Abstract

In linear IC´s fabricated in a low-voltage CMOS technology, the reduction of the dynamic range due to the dc offset and low frequency noise of the amplifiers becomes increasingly significant. Also, the achievable amplifier gain is often quite low in such a technology, since cascoding may not be a practical circuit option due to the resulting reduction of the output signal swing. In this paper, some old and some new circuit techniques are described for the compensation of the amplifier´s most important nonideal effects including the noise (mainly thermal and 1/f noise), the input-referred dc offset voltage as well as the finite gain resulting in a nonideal virtual ground at the input

Keywords

1/f noise; CMOS analogue integrated circuits; choppers (circuits); circuit stability; compensation; integrated circuit noise; operational amplifiers; thermal noise; 1/f noise; amplifier gain; autozeroing; chopper stabilization; circuit techniques; compensation; correlated double sampling; dc offset; dynamic range; finite gain; input-referred dc offset voltage; linear ICs; low frequency noise; low-voltage CMOS technology; nonideal effects; nonideal virtual ground; op-amp imperfections; output signal swing reduction; thermal noise; CMOS technology; Choppers; Circuit noise; Dynamic range; Frequency; Low-frequency noise; Noise reduction; Operational amplifiers; Sampling methods; Voltage;

fLanguage

English

Journal_Title

Proceedings of the IEEE

Publisher

ieee

ISSN

0018-9219

Type

jour

DOI

10.1109/5.542410

Filename

542410