A two-stage low-power amplifier with switch-capacitor common-mode feedback circuits

Author

Lei Zhang ; Rongbin Hu ; Can Zhu ; Yonglu Wang ; Zhengping Zhang ; Rongke Ye ; Yuhan Gao

Author_Institution

No.24 Res. Inst., China Electron. Technol. Group Corp., Chongqing, China

fYear

2014

fDate

16-23 Aug. 2014

Firstpage

1

Lastpage

4

Abstract

A low-power amplifier is designed to improve the performances of ADCs. The two-stage construction is adopted to provide bigger gain and wider swing at a power supply lower than 3.3V. Besides, the differential architecture is adopted to double the output swing while suppressing common noises. Special common-mode feedback circuits are designed to stable the common-mode outputs of the first and second stages but not to degenerate the output swing. A private switch is designed for the common-mode feedback circuits to eliminate the charge injection effect on the common-mode signals. The measurement results show that the ADC using the proposed amplifier has a SNR which is 4dB better than the ADC without the proposed amplifier.

Keywords

MIS devices; analogue-digital conversion; charge injection; feedback amplifiers; interference suppression; switched capacitor networks; ADC performance improvement; SNR; charge injection effect elimination; common noise suppression; common-mode signal; differential architecture; output swing; power supply; private switch; switch-capacitor common-mode feedback circuit; two-stage low-power amplifier; Capacitors; Feedback circuits; Logic gates; MOSFET; Power supplies; Signal to noise ratio; Switching circuits;

fLanguage

English

Publisher

ieee

Conference_Titel

General Assembly and Scientific Symposium (URSI GASS), 2014 XXXIth URSI

Conference_Location

Beijing

Type

conf

DOI

10.1109/URSIGASS.2014.6929334

Filename

6929334