A low-offset class-AB CMOS operational amplifier

Author

Chan, P.K. ; Siek, L. ; Tay, H.C. ; Su, J.H.

Author_Institution

Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore

Volume

3

fYear

2000

fDate

2000

Firstpage

455

Abstract

This paper presents a novel systematic offset minimization circuit for designing a class-AB CMOS operational amplifier. The proposed structure has a replica-gain circuit, generating a DC replica bias to the differential input stage, and providing differential gain as well as level conversion to drive the class-AB output stage. Statistical measurements on 15 samples of the amplifier showed the mean and standard deviation of the input offset were of 0.88 mV and 0.49 mV respectively. These results were achieved using an active area of only 3700 μm² for the critical differential input stage in a 0.8 μm standard CMOS technology

Keywords

CMOS analogue integrated circuits; differential amplifiers; minimisation; operational amplifiers; 0.8 micron; CMOS operational amplifier; DC replica bias; class-AB op amp; differential gain; differential input stage; level conversion; low-offset op amp; offset minimization circuit; replica-gain circuit; CMOS technology; Character generation; Circuit noise; Current density; Design engineering; Differential amplifiers; Minimization; Mirrors; Operational amplifiers; Temperature sensors;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 2000. Proceedings. ISCAS 2000 Geneva. The 2000 IEEE International Symposium on

Conference_Location

Geneva

Print_ISBN

0-7803-5482-6

Type

conf

DOI

10.1109/ISCAS.2000.856095

Filename

856095