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Design >> Mixed-Signal Design >> calculating feedback coefficients of ADC
https://designers-guide.org/forum/YaBB.pl?num=1325170748

Message started by singh on Dec 29^th, 2011, 6:59am

Title: calculating feedback coefficients of ADC
Post by singh on Dec 29^th, 2011, 6:59am

can someone help with the calculation of coefficients a1,a2,b1,b2 of 2nd order sigma delta ADC attached in the picture?

resolution required = 14 bit
filter = 2 integrators
n = 537 cycles

please gimme any reference if possible.

thanks

Title: Re: calculating feedback coefficients of ADC
Post by Dan Clement on Dec 29^th, 2011, 9:13am

Can't you just use the sigma delta toolbox in Matlab?

Title: Re: calculating feedback coefficients of ADC
Post by raja.cedt on Dec 29^th, 2011, 10:07am

do you have NTF,STF with you? please post them so that it is very easy to estimate ...

Thanks,
Raj.

Title: Re: calculating feedback coefficients of ADC
Post by ywguo on Dec 30^th, 2011, 7:38am

Hi Singh,

Do u know Undersanding Delta-Sigma Data Convertors by Richard Schreier and Gabor C. Teems?
Please click the link http://www.designers-guide.org/Books/#Schreier-2004.
A matlab toolbox named delsig is appendix in that book. The source code can be downloaded from mathworks. It has some functions that synthesize and evaluate the performance. It is a good start to decide the coefficients.