An Ultralow-Power Low-Voltage Class-AB Fully Differential OpAmp for Long-Life Autonomous Portable Equipment

Author

Bernal, María Rodanas Valero ; Celma, S. ; Medrano, N. ; Calvo, B.

Author_Institution

Group of Electron. Design (I3A), Univ. of Zaragoza, Zaragoza, Spain

Volume

59

Issue

10

fYear

2012

Firstpage

643

Lastpage

647

Abstract

This brief presents an ultralow-power class-AB operational amplifier (OpAmp) designed in a low-cost 0.18- μm CMOS technology. The proposed circuit uses transistors biased in the subthreshold region for low-voltage low-power operation. For a 0.8-V single supply, this OpAmp has 51-dB open-loop gain, 57-kHz unity-gain frequency, 60° phase margin, and 65-dB common-mode rejection ratio for 8-pF loads with a power consumption of only 1.2 μW. Experimental results illustrate performances such as a 0.14-V/μs slew rate and a 750-mV linear output swing, demonstrating its correct functionality.

Keywords

CMOS analogue integrated circuits; differential amplifiers; low-power electronics; operational amplifiers; transistor circuits; CMOS analog integrated circuit; CMOS technology; OpAmp; common-mode rejection ratio; frequency 57 kHz; gain 51 dB; linear output swing; long-life autonomous portable equipment; low-voltage low-power operation; open-loop gain; power 1.2 muW; size 0.18 mum; subthreshold region; transistor; ultralow-power low-voltage class-AB fully differential operational amplifier; unity-gain frequency; voltage 0.8 V; voltage 750 mV; CMOS integrated circuits; Computational modeling; Gain; Integrated circuit modeling; MOS devices; Strontium; Transistors; CMOS analog integrated circuits; low-power design; operational amplifiers (OpAmps);

fLanguage

English

Journal_Title

Circuits and Systems II: Express Briefs, IEEE Transactions on

Publisher

ieee

ISSN

1549-7747

Type

jour

DOI

10.1109/TCSII.2012.2213361

Filename

6294513