Title :
High EMI immunity CMOS opamp: design and measurements
Author :
Richelli, A. ; Colalongo, L. ; Kovacs-Vajna, Zs ; Quarantelli, M.
Author_Institution :
Dept. of Electron., Brescia Univ., Italy
Abstract :
In this paper, a new approach to design a CMOS operational amplifier is presented which provides a good trade-off between high gain and strong immunity to electromagnetic interferences. The proposed amplifier is based on two main blocks: the first is a fully differential folded cascode amplifier with modified differential input pair and the second is a source cross coupled AB class buffer. Thanks to the folded cascade stage and to the symmetrical output buffer, the amplifier exhibits both intrinsic robustness to interferences and good amplifier performances. The circuit was fabricated in a 0.8μm n-well CMOS technology (AMS CYE process). Experimental results, in terms of EMI immunity, are presented and successfully compared to commercial amplifiers. Measurements carried out on the chip and the amplifier overall performances are provided along with the corresponding simulation results.
Keywords :
CMOS integrated circuits; electromagnetic interference; integrated circuit design; operational amplifiers; 0.8 microns; AB class buffer; AMS CYE process; CMOS technology; EMI immunity; electromagnetic interferences; folded cascode amplifier; modified differential input pair; operational amplifier; symmetrical output buffer; CMOS process; CMOS technology; Coupling circuits; Differential amplifiers; Electromagnetic interference; Electromagnetic measurements; Operational amplifiers; Performance evaluation; Robustness; Semiconductor device measurement;
Conference_Titel :
Electromagnetic Compatibility, 2003 IEEE International Symposium on
Print_ISBN :
0-7803-7835-0
DOI :
10.1109/ISEMC.2003.1236595
