Title :
An efficient design method for the modulator of high-order ΣΔ ADCs
Author :
Chen, Jhy-Rong ; Kuo, Tai-Haur
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
An exquisite high-order sigma delta (ΣΔ) modulator for specific application is hard to be achieved by a less experienced designer formerly. Now, a novel and efficient design method for high-order lowpass and bandpass ΣΔ modulators is proposed. To begin with, the noise transfer function (NTF) of a ΣΔ modulator is chosen from the transfer functions of the conventional analog filters. Rigorous stability constraints are employed to examine the NTF. Modulator parameters including oversampling ratio (OSR), number of the modulator order, and loop gain of the NTF are determined by system specifications. Thus, a modulator which fits the specific application with most economic system design parameters and minimum in-band harmonic distortion will be easily achieved
Keywords :
circuit stability; modulators; network synthesis; sigma-delta modulation; transfer functions; bandpass ΣΔ modulators; design method; high-order ΣΔ ADCs; high-order sigma delta modulator; loop gain; lowpass ΣΔ modulators; minimum in-band harmonic distortion; modulator order number; modulator parameters; noise transfer function; oversampling ratio; stability constraints; Band pass filters; Cities and towns; Delta modulation; Delta-sigma modulation; Design methodology; Harmonic distortion; Sampling methods; Signal to noise ratio; Stability; Transfer functions;
Conference_Titel :
Circuits and Systems, 1996. ISCAS '96., Connecting the World., 1996 IEEE International Symposium on
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-3073-0
DOI :
10.1109/ISCAS.1996.539795
