A general description of common-mode feedback in fully-differential amplifiers

Author

VanPeteghem, P.M. ; Duque-Carrillo, J.F.

Author_Institution

Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA

fYear

1990

fDate

1-3 May 1990

Firstpage

320

Abstract

Fully-differential amplifiers and their common-mode feedback (CMFB) loops are described, and the impact of CMFB loop mismatching on common mode rejection ratio (CMRR) noise and distortion is discussed. A set of gain parameters which are suitable for predicting the actual performance of such a balanced amplifier is defined. The presented formalism takes mismatching and nonlinearity in the CMFB loop into account. The gain parameters can easily be calculated or simulated for different circuit configurations. It is concluded that the common-mode sense circuits can have a major impact on the accuracy of the differential mode signal processing

Keywords

differential amplifiers; feedback; network analysis; CMFB loop mismatching; balanced amplifier; common mode rejection ratio; common-mode feedback; common-mode sense circuits; differential mode signal processing; distortion; fully-differential amplifiers; gain parameters; Analog integrated circuits; Delta modulation; Feedback loop; Instruments; Integrated circuit noise; Low voltage; Operational amplifiers; Output feedback; Signal processing; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 1990., IEEE International Symposium on

Conference_Location

New Orleans, LA

Type

conf

DOI

10.1109/ISCAS.1990.112716

Filename

112716