Title :
A new architecture for rail-to-rail input constant-gm CMOS operational transconductance amplifiers
Author :
Ahmadi, Mohammad M. ; Lotfi, Reza ; Sharif-Bakhtiar, Mehrdad
Author_Institution :
Dept. of Electr. Eng., Sharif Univ. of Technol., Tehran, Iran
Abstract :
A new architecture for constant-gm, rail-to-rail(R-R) input stages is presented that has less than 5% deviation in gm over the entire range of the input common-mode voltage. Furthermore, a new structure for folded cascode amplifier based on the use of a floating current source is presented. Employing these techniques a low-power operational transconductance amplifier (OTA) with 100 MHz unity-gain bandwidth, 106 dB gain, 60° phase margin, 2.65 V swing, and 6.4 nV/√Hz input-referred noise with R-R input common-mode range is realized in a 0.8 μm CMOS technology. This amplifier dissipates 10 mW from a 3V power supply.
Keywords :
CMOS analogue integrated circuits; integrated circuit design; low-power electronics; operational amplifiers; pole assignment; zero assignment; 1 mW; 106 dB; 3 V; CMOS OTA; circuit architectures; current summation; floating current source; folded cascode amplifier; input common-mode voltage; low-power amplifier; pole-zero locations; rail-to-rail input stages; Bandwidth; CMOS technology; Gain; Low-noise amplifiers; Operational amplifiers; Phase noise; Power amplifiers; Rail to rail inputs; Transconductance; Voltage;
Conference_Titel :
Low Power Electronics and Design, 2003. ISLPED '03. Proceedings of the 2003 International Symposium on
Print_ISBN :
1-58113-682-X
DOI :
10.1109/LPE.2003.1231913
