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Finding the right DSP evaluation board

Started by Zach R. August 28, 2003
Hi everyone,
  I am looking for a floating point evaluation board that has easy
audio inputs (such as rca or 3.5mm jacks) and a SAR adc.  I have
almost exactly what I want in the ADSP BF533 but I am getting a group
delay due to the sigma-delta converter.  Some of you on here let me
know that I needed to use a SAR adc for feedback control applications.
 So I need to find a new evaluation board with similar characteristics
as the BF533 but w/ the SAR adc.

Thanks for your help,
Zach
"Zach R." wrote:
> > Hi everyone, > I am looking for a floating point evaluation board that has easy > audio inputs (such as rca or 3.5mm jacks) and a SAR adc. I have > almost exactly what I want in the ADSP BF533 but I am getting a group > delay due to the sigma-delta converter. Some of you on here let me > know that I needed to use a SAR adc for feedback control applications. > So I need to find a new evaluation board with similar characteristics > as the BF533 but w/ the SAR adc. > > Thanks for your help, > Zach
Probably the most straightforward way is to ignore the on-board converter and kludge on your own. Use an address decoder on the expansion connector. (You can add extra memory while you're at it. The cache chips from an old motherboard are worth looking at.) Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������

"Zach R." wrote:
> > Hi everyone, > I am looking for a floating point evaluation board that has easy
BF is not a floating point engine. I assume the fp capabilities are not critical for you.
> audio inputs (such as rca or 3.5mm jacks) and a SAR adc.
That is contradictory. All audio ADCs that I know are of delta-sigma type. The typical pipelining delay is several dozens of sample rate periods.
> almost exactly what I want in the ADSP BF533 but I am getting a group > delay due to the sigma-delta converter.
You can boost up the sample rate to reduce the delay to acceptable, or you can attach the SAR ADC of your own.
> So I need to find a new evaluation board with similar characteristics > as the BF533 but w/ the SAR adc.
Why can't you use just a microcontroller with built-in SAR instead of DSP? There are numerous eval boards available. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
> > Thanks for your help, > Zach