Title :
Fully-differential CMOS current-mode circuits and applications
Author :
Zele, Rajesh H. ; Allstot, David J. ; Fiez, Terri S.
Author_Institution :
Dept. of Electr. & Comput. Eng., Carnegie Mellon Univ., Pittsburgh, PA, USA
Abstract :
A CMOS fully differential current-mode analog signal processing technique has been developed. The basic building block, a 5-V fully differential current-mode operational amplifier (I-OPAMP), has been integrated using the MOSIS 2 μm n-well CMOS technology. Measured total harmonic distortion (THD) is -70 B with a peak signal (1) to a bias current (Iˆ) ratio of 0.5. By simply adding MOS switches, the I- OPAMP topology is easily extended to implement fully differential switched-current (SI) circuits with first-order cancellation of clock-feedthrough effects. A five-pole Chebyshev lowpass fully differential SI ladder filter has also been integrated in the 2 μm p-well CMOS technology. Measured results show that with a sampling frequency of 128 kHz, the desired ripple bandwidth of 5 kHz is accurately realized using the fully differential SI structure
Keywords :
CMOS integrated circuits; active networks; differential amplifiers; ladder networks; linear integrated circuits; low-pass filters; operational amplifiers; 128 kHz; 2 micron; 5 V; CMOS; MOS switches; MOSIS; analog signal processing technique; clock-feedthrough effects; current-mode circuits; first-order cancellation; five-pole Chebyshev lowpass; fully differential op amp; ladder filter; n-well CMOS technology; operational amplifier; p-well CMOS technology; CMOS process; CMOS technology; Current mode circuits; Differential amplifiers; Distortion measurement; Integrated circuit measurements; Integrated circuit technology; Operational amplifiers; Signal processing; Switching circuits;
Conference_Titel :
Circuits and Systems, 1991., IEEE International Sympoisum on
Print_ISBN :
0-7803-0050-5
DOI :
10.1109/ISCAS.1991.176758
