Title :
A 1 V Switched-Capacitor /spl Sigma//spl Delta/ modulator
Author :
Bazarjani, S.S. ; Snelgrove, M. ; MacElwee, T.
Author_Institution :
Dept. of Electron., Carleton Univ., Ottawa, Ont., Canada
Abstract :
This paper describes a 1 V first order Switched-Capacitor (SC) /spl Sigma//spl Delta/ modulator implemented in a 0.5 /spl mu/m n+/p+ dual poly gate CMOS process using natural threshold voltage MOSFETs. The natural transistors in this process have threshold voltages of about 180 mV (nMOSFETs) and 200 mV (pMOSFETs) which is suitable for 1 V circuits. Modification to the process is minimal and involves the removal of the threshold adjust implant step. This modulator operates at 1 V and has 54 dB dynamic range for an oversampling ratio of 128 (sampling frequency 1 MHz and signal frequency 4 KHz) and consumes about 100 /spl mu/W.
Keywords :
CMOS integrated circuits; sigma-delta modulation; switched capacitor networks; 0.5 micron; 1 V; 100 muW; MOSFETs; dynamic range; low voltage circuit; n+/p+ dual poly gate CMOS process; natural transistors; oversampling ratio; switched-capacitor /spl Sigma//spl Delta/ modulator; threshold voltages; CMOS process; CMOS technology; Circuits; Delta modulation; Dynamic range; Implants; Low voltage; MOSFETs; Telecommunication switching; Threshold voltage;
Conference_Titel :
Low Power Electronics, 1995., IEEE Symposium on
Conference_Location :
San Jose, CA, USA
Print_ISBN :
0-7803-3036-6
DOI :
10.1109/LPE.1995.482468
