On the relationship between the CMRR or PSRR and the second harmonic distortion of differential input amplifiers

Author

Eynde, Frank Op´t ; Wambacq, Piet ; Sansen, Willy

Author_Institution

Dept. of Electron., Catholic Univ. of Leuven, Heverlee, Belgium

Volume

24

Issue

6

fYear

1989

fDate

12/1/1989 12:00:00 AM

Firstpage

1740

Lastpage

1744

Abstract

The results of a harmonic distortion analysis for a differential pair are presented, including the effects of mismatches and of the finite nonlinear common-mode rejection ratio (CMRR) or power-supply rejection ratio (PSRR). Due to mismatches, a differential pair produces second-harmonic distortion. The presence of a finite common-mode gain limits the amount of feedback which can be usefully applied to suppress the harmonic distortion. When the common-mode gain is nonlinear, additional distortion is generated which is not suppressed by the feedback. When the amplifier has to drive a large load and when the supply line impedance is large, the finite PSRR causes similar effects

Keywords

differential amplifiers; electric distortion; feedback; PSRR; common-mode rejection ratio; differential input amplifiers; distortion suppression; finite nonlinear CMRR; mismatches; negative feedback; power-supply rejection ratio; second harmonic distortion; Circuit testing; Differential amplifiers; Distortion measurement; Frequency; Harmonic analysis; Harmonic distortion; Impedance; Negative feedback; Power amplifiers; Voltage;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/4.45014

Filename

45014