Title :
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
fDate :
11/1/1996 12:00:00 AM
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;
Journal_Title :
Proceedings of the IEEE
