Common mode stability in fully differential voltage feedback CMOS amplifiers

Author

Tauro, Arturo ; Marzocca, Cristoforo ; Francesco, C.T. ; Giandomenico, Antonio Di

Author_Institution

Dipt. di Elettrotecnica ed Elettronica, Politecnico di Bari, Italy

Volume

1

fYear

2003

fDate

14-17 Dec. 2003

Firstpage

288

Abstract

In this study consideration is made of the common mode (CM) behavior of two-stage fully differential amplifiers in voltage feedback (FB) connection. In particular, the interaction between internal CMFB circuitry and the external feedback network is investigated in order to highlight a possible operating point instability condition, due to the presence of a positive feedback loop. Two alternative CMFB topologies are compared, one of which is affected by instability, with development of constraints on the feedback network parameters to be fulfilled in order to avoid instability. Comparison was made by circuit simulations with reference to a low voltage, deep sub-micron CMOS technology (0.12 μm) implementation of a differential amplifier.

Keywords

CMOS analogue integrated circuits; circuit simulation; circuit stability; differential amplifiers; feedback amplifiers; integrated circuit modelling; low-power electronics; 0.12 micron; CMOS amplifiers; common mode stability; feedback network parameter constraints; fully differential amplifiers; low voltage CMOS technology; operating point instability condition; positive feedback loop; two-stage differential amplifiers; voltage feedback amplifiers; CMOS technology; Circuit simulation; Circuit topology; Differential amplifiers; Feedback circuits; Feedback loop; Low voltage; Network topology; Power amplifiers; Stability;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics, Circuits and Systems, 2003. ICECS 2003. Proceedings of the 2003 10th IEEE International Conference on

Print_ISBN

0-7803-8163-7

Type

conf

DOI

10.1109/ICECS.2003.1302033

Filename

1302033