A bulk-driven CMOS OTA with 68 dB DC gain

Author

Rosenfeld, Jonathan ; Kozak, Mücahit ; Friedman, Eby G.

Author_Institution

Dept. of Electr. & Comput. Eng., Rochester Univ., NY, USA

fYear

2004

fDate

13-15 Dec. 2004

Firstpage

5

Lastpage

8

Abstract

An ultra-low voltage rail-to-rail operational transconductance amplifier, (OTA) based on a standard digital 0.18 μm CMOS process, is described in this paper. Techniques for designing a 0.8 V fully differential OTA are discussed, including bias and reference current generator circuits. To achieve rail-to-rail operation, complementary input differential pairs are used, where the bulk-driven technique is applied to reduce the threshold limitation of the MOSFET transistors. The OTA gain is increased by using auxiliary gain boosting amplifiers. This additional circuitry enables the OTA to operate at 0.8 V, achieving an open loop gain of 68 dB while consuming 94 μW. The DC gain of the amplifier is the highest gain achieved to date in bulk-driven amplifiers.

Keywords

CMOS analogue integrated circuits; differential amplifiers; low-power electronics; operational amplifiers; 0.18 micron; 0.8 V; 68 dB; 94 muW; MOSFET transistor threshold limitation; auxiliary gain boosting amplifiers; bias current generator circuits; bulk-driven CMOS OTA; bulk-driven technique; complementary input differential pairs; fully differential OTA; open loop gain; operational transconductance amplifier; rail-to-rail operation; reference current generator circuits; ultra-low voltage amplifier; Analog circuits; Boosting; CMOS technology; Contracts; Gain; MOSFET circuits; Operational amplifiers; Rail to rail operation; Threshold voltage; Transconductance;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics, Circuits and Systems, 2004. ICECS 2004. Proceedings of the 2004 11th IEEE International Conference on

Print_ISBN

0-7803-8715-5

Type

conf

DOI

10.1109/ICECS.2004.1399600

Filename

1399600