Title :
5mW 64dB SNDR 4th order bandpass ΣΔ modulator for 10.7MHz digital IF
Author :
Noman, Ahmed ; Sharaf, Khaled ; Ragai, Hany Fikry
Author_Institution :
RFIC Group, MEMSCAP, Durham, NC, USA
Abstract :
A 5 mW 4th order SC bandpass sigma delta modulator is designed in 0.8 μm CMOS process. An SNDR of 64.8 dB over 200 kHz and image rejection better than 0 dB are achieved by adapting double sampling technique in circulating delay type resonator. The resonator is built using a high performance gain boosted folded cascode opamp. An improved SC CMFB circuit is proposed to support double sampling requirements. The opamp achieves 106 dB of DC gain 10 MHz GBW with 750 mA current 3V supply.
Keywords :
CMOS integrated circuits; band-pass filters; circuit feedback; operational amplifiers; sigma-delta modulation; switched capacitor networks; 0.8 micron; 10.7 MHz; 106 dB; 200 kHz; 3 V; 4th order bandpass ΣΔ modulator; 5 mW; 750 mA; CMOS process; SC CMFB circuit; circulating delay type resonator; double sampling technique; folded cascode opamp; Circuit noise; Delta modulation; Delta-sigma modulation; Digital filters; Digital modulation; Dynamic range; Energy consumption; Frequency; Image sampling; Sampling methods;
Conference_Titel :
Circuits and Systems, 2003 IEEE 46th Midwest Symposium on
Print_ISBN :
0-7803-8294-3
DOI :
10.1109/MWSCAS.2003.1562232
