Title :
A global operational amplifier with constant-gm input and output stage
Author :
Chang, Il Kwon ; Park, Jang Woo ; Kim, Se Jun ; Kwack, Kae Dal
Author_Institution :
Dept. of Electron. Eng., Hanyang Univ., Seoul, South Korea
Abstract :
The principle and design of a 3 V two-stage CMOS operational amplifier are described. A rail-to-rail input stage shows almost constant transconductance independent of the common mode input voltage range with global transistor operation region. This new technique does not make use of accurate current-voltage relations of MOS transistors. Hence it can be applicable to a simple linear relationship of currents. The proposed global two-stage op-amp also can operate both in strong inversion and in weak inversion. Class AB output stage proposed also has a full output voltage swing and a well-defined quiescent current that does not depend on power supply voltage
Keywords :
CMOS analogue integrated circuits; constant current sources; operational amplifiers; summing circuits; 3 V; common mode input voltage range; constant transconductance; constant-gm input/output stage; full output voltage swing; global operational amplifier; global transistor operation region; linear relationship; quiescent current; rail-to-rail input stage; strong inversion; two-stage CMOS operational amplifier; weak inversion; Dynamic range; Low voltage; MOS devices; Mirrors; Operational amplifiers; Rail to rail inputs; Rail to rail operation; Switches; Transconductance; Voltage control;
Conference_Titel :
TENCON 99. Proceedings of the IEEE Region 10 Conference
Conference_Location :
Cheju Island
Print_ISBN :
0-7803-5739-6
DOI :
10.1109/TENCON.1999.818603
