Title :
A dual phase SC CMFB circuit for double sampling modulators
Author :
Noman, Ahmed ; Dessouky, Mohamed ; Sharaf, Khaled
Author_Institution :
RFIC Group, Ain Shams Univ., Cairo, Egypt
Abstract :
A dual phase switched capacitor common mode feedback (SC CMFB) circuit is proposed which is suitable for double sampling circuits. A 4th order SC bandpass sigma delta modulator designed in CMOS is used as a testbench to compare the proposed circuit to conventional SC CMFB. The proposed circuit achieves 33 dB better image rejection and enhances the SNDR over 200 kHz bandwidth compared to the same circuit then simulated with conventional single phase switched capacitor common mode feedback.
Keywords :
CMOS integrated circuits; band-pass filters; circuit feedback; sigma-delta modulation; switched capacitor networks; CMOS technology; bandpass sigma delta modulator; double sampling circuits; double sampling modulators; dual phase switched capacitor common mode feedback circuit; Bandwidth; Circuit testing; Delta modulation; Delta-sigma modulation; Feedback circuits; Image sampling; Phase modulation; Sampling methods; Switched capacitor circuits; Switching circuits;
Conference_Titel :
Circuits and Systems, 2003 IEEE 46th Midwest Symposium on
Print_ISBN :
0-7803-8294-3
DOI :
10.1109/MWSCAS.2003.1562275
