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Design >> Mixed-Signal Design >> DEM for Delta Sigma ADC (3rd order SC based)
https://designers-guide.org/forum/YaBB.pl?num=1311765970

Message started by harpoon on Jul 27^th, 2011, 4:26am

Title: DEM for Delta Sigma ADC (3rd order SC based)
Post by harpoon on Jul 27^th, 2011, 4:26am

Hi all,

I will be working on a Dynamic Element Matching (DEM) scheme for a SC based 3rd order Delta Sigma ADC.

Can someone give me some "real-world" pointers ? what are the pitfalls, pros and cons, reference papers, etc ...

btw, I am reading "Understanding Delta-Sigma Data Converters" by R. Schreier & G. Temes

Thanks.

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by jefkat on Sep 20^th, 2011, 1:10am

Have you found some links yet?

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by harpoon on Sep 20^th, 2011, 2:05am

There are a lot of published work, each with their own merits. However, I am really after some real world feedback, i.e. what are the pitfalls.

There are several schemes that I have tested in Matlab, but they don't seem to work that well. My ex-colleague has put together several schemes but failed to get them to work.

You seem to have something new and interesting ?

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by ywguo on Sep 20^th, 2011, 7:27am

I recommend CMOS Integrated Analog-to-Digital and Digital-to-Analog Converters by Rudy J. van de Plassche.
http://www.designers-guide.org/Books/#vanDePlassche-2003

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by harpoon on Sep 21^st, 2011, 2:30am

Thanks ... that book was published in 2003 ...

Are there any new stuff published since then ?

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by jefkat on Sep 21^st, 2011, 11:18am

how many levels do you have in quantizer/DAC?

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by harpoon on Sep 22^nd, 2011, 2:19am

we have a 9 level quantizer (3bit quantizer/dac).

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by jefkat on Sep 23^rd, 2011, 12:51am

Could you please explain what problem are you facing ? DEM for 9 levels works fine. What order of error shaping are you trying to achieve?

Title: Re: DEM for Delta Sigma ADC (3rd order SC based)
Post by harpoon on Sep 23^rd, 2011, 6:08am

My colleague implemented a DEM scheme which seemed to work in simulation but not in real life. I have also implemented a simpler DEM scheme which also works in simulation ... but I am a bit cautious of whether it will work in the silicon !

Just wanted to see if others have faced similar issues and what the cause could be ...