Title :
An high-swing, 1.8 V, push-pull opamp for sigma-delta modulators
Author :
Malcovati, Piero ; Maloberti, Franco ; Terzani, Maurizio
Author_Institution :
Integrated Microsyst. Lab., Pavia Univ., Italy
Abstract :
This paper presents a push-pull, fully-differential operational amplifier capable of operating with a 1.8 V power supply. The circuit uses a novel approach to drive the class AB output stage based on two fully differential operational transconductance amplifiers. Moreover, it includes a dynamic biasing circuit to improve the slew-rate as well as continuous-time and switched-capacitor common-mode feedback circuits to control the output common-mode voltage and the quiescent current in the output stage. Good performance and valuable noise characteristics are achieved
Keywords :
CMOS analogue integrated circuits; differential amplifiers; feedback amplifiers; low-power electronics; operational amplifiers; sigma-delta modulation; switched capacitor networks; 0.5 micron; 0.6 mW; 1.8 V; 94 dB; CMOS technology; OTA; SC common-mode feedback circuit; class AB output stage; continuous-time CMFB circuit; dynamic biasing circuit; fully-differential operational amplifier; high-swing opamp; noise characteristics; operational transconductance amplifier; output common-mode voltage control; push-pull opamp; quiescent current control; sigma-delta modulators; slew-rate improvement; switched-capacitor CMFB circuits; Circuit noise; Delta-sigma modulation; Differential amplifiers; Feedback circuits; Operational amplifiers; Power amplifiers; Power supplies; Switching circuits; Transconductance; Voltage control;
Conference_Titel :
Electronics, Circuits and Systems, 1998 IEEE International Conference on
Conference_Location :
Lisboa
Print_ISBN :
0-7803-5008-1
DOI :
10.1109/ICECS.1998.813265
