Title :
A low-voltage low-power CMOS opamp with rail-to-rail input/output
Author :
Lin, Chi-Hung ; Ismail, Mohammed
Author_Institution :
Dept. of Electr. Eng., Ohio State Univ., Columbus, OH, USA
Abstract :
In this paper, a low-voltage low-power two stage rail-to-rail CMOS opamp is presented. The input stage is composed of the complementary differential pairs and a pair of modified current-mode maximum selecting circuits (Maximum Current Selecting Circuit II) in order to achieve rail-to-rail operation and constant-gm. Using the modified constant-gm methodology, this input stage co-operated with a family of two class-AB output stages can drive a wide-range of capacitive loads with a large bandwidth-to-supply-power ratio. These opamps reach a high DC gain (≥84 dB), and have a bandwidth-to-supply-power ratio of 13 MHz/mW and 9.5 MHz/mW with capacitive loads 20 pF and 100 pF respectively.
Keywords :
CMOS analogue integrated circuits; differential amplifiers; operational amplifiers; 84 dB; class-AB output stages; complementary differential pairs; current-mode maximum selecting circuits; low-power CMOS opamp; low-voltage op amp; modified constant-gm methodology; rail-to-rail input/output; Circuits; Costs; Energy consumption; Frequency; MOSFETs; Power dissipation; Rail to rail inputs; Rail to rail outputs; Very large scale integration; Wideband;
Conference_Titel :
Circuits and Systems, 1997. Proceedings of the 40th Midwest Symposium on
Print_ISBN :
0-7803-3694-1
DOI :
10.1109/MWSCAS.1997.662293
