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Design >> Mixed-Signal Design >> can anyone recommend me a good NTF function for DSM?
https://designers-guide.org/forum/YaBB.pl?num=1265293565

Message started by Lancelot on Feb 4^th, 2010, 6:26am

Title: can anyone recommend me a good NTF function for DSM?
Post by Lancelot on Feb 4^th, 2010, 6:26am

Hi, guys,

I hope to design a CT DSM with OSR=8 to reduce the sampling frequency, and the ENOB should be above 12bits. originally, i want to adopt a 4 orders 4 bits architecture, and insert a zero inside the signal BW to improve the SNR. But it's not easy to choose a suitable NTF and the coefficients. can anyone give me some suggestions?

Title: Re: can anyone recommend me a good NTF function for DSM?
Post by Berti on Feb 4^th, 2010, 7:49am

Unless you know what you do I would recommend to use Richard Schreiers Delta-Sigma Toolbox to design the NTF and transform the result in a continuous-time filter.

By the way, I am not so sure whether minimizing the OSR is a good idea, unless it is required due to jitter requirements. By minimizing the OSR of a continuous-time modulator you loose an advantage over discrete-time modulators.

Regards