A 0.8 V quasi-floating-gate fully differential CMOS op-amp with positive feedback

Author

Thongleam, Thawatchai ; Suadet, Apirak ; Kasemsuwan, Varakom

Author_Institution

Sch. of Electron., King Mongkut´´s Inst. of Technol. Ladkrabang, Bangkok, Thailand

fYear

2011

fDate

17-19 May 2011

Firstpage

98

Lastpage

101

Abstract

This paper presents a 0.8 V fully differential CMOS op-amp. The input stage of the circuit is designed using quasi-floating-gate (QFG) transistors with positive feedback, while QFG transistors in the output stage are connected in the class AB configuration. QFG transistors are employed, enabling the circuit to operate under low supply voltage. The proposed amplifier is designed using 0.18 μm CMOS technology, and simulation results show rail-to-rail input and output swings. The open-loop gain is 80.4 dB with the gain-bandwidth product of 8.66 MHz. Phase margin is 45° (C_L= 20 pF). The CMRR is 107 dB (at 1 kHz) and the power consumption is 54.9 μW.

Keywords

CMOS analogue integrated circuits; differential amplifiers; integrated circuit design; operational amplifiers; class AB configuration; frequency 1 kHz; frequency 8.66 MHz; gain 80.4 dB; positive feedback; power 54.9 muW; quasi-floating-gate fully differential CMOS op-amp; quasi-floating-gate transistors; size 0.18 mum; voltage 0.8 V; CMOS integrated circuits;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON), 2011 8th International Conference on

Conference_Location

Khon Kaen

Print_ISBN

978-1-4577-0425-3

Type

conf

DOI

10.1109/ECTICON.2011.5947780

Filename

5947780