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Hi!

I've been working with a 6713DSK but realized that the delay 
introduced by the codec is far to large (about 1.25 ms @ 22.05 ksps). 
I'm trying to find a developer kit (doesn't care about manufacturer) 
that uses a codec/ADC-DAC which doesn't introduce more than, say, 0.5-
1 ms delay. I guess this implies a SAR-ADC instead of a Sigma-Delta 
approach. However, finding a complete developer kit with this type of 
codec seems to be hard. Does anyone have any suggestions?

Best regards,
/Nils

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Nils-

> I've been working with a 6713DSK but realized that the delay
> introduced by the codec is far to large (about 1.25 ms @ 22.05 ksps).
> I'm trying to find a developer kit (doesn't care about manufacturer)
> that uses a codec/ADC-DAC which doesn't introduce more than, say, 0.5-
> 1 ms delay. I guess this implies a SAR-ADC instead of a Sigma-Delta
> approach. However, finding a complete developer kit with this type of
> codec seems to be hard. Does anyone have any suggestions?

Maybe try one of the daughtercards available for 6713 DSK:

http://focus.ti.com/dsp/docs/dspsupporttoolssoftwareaut.tsp?sectionId=3&tabId=466&toolT
ypeId=48&familyId=132

Note that "daughter cards" from Pentek, Innovative, Surf, Signatec, and a few others
are actually PMC or other form-factor modules that do not mate with DSK boards (have
no idea how they got on this page, which says "...connect with TI DSP Starter Kits
(DSKs)...").

-Jeff

(You need to be a member of audiodsp -- send a blank email to audiodsp-subscribe@yahoogroups.com )

Even using a non-oversampled SAR-based ADC doesn't guarantee low
latency.. Unless you oversample, the SAR-based ADC will require a front
end low pass filter with a steep rolloff approaching FS/2. Along with
the steep rolloff comes a bump in the group delay near or at the LPF
corner frequency. Before committing to this course, get data for group
delay from the vendor or design references.

Chris

Jeff Brower wrote:
> Nils-
>
>   
>> I've been working with a 6713DSK but realized that the delay
>> introduced by the codec is far to large (about 1.25 ms @ 22.05 ksps).
>> I'm trying to find a developer kit (doesn't care about manufacturer)
>> that uses a codec/ADC-DAC which doesn't introduce more than, say, 0.5-
>> 1 ms delay. I guess this implies a SAR-ADC instead of a Sigma-Delta
>> approach. However, finding a complete developer kit with this type of
>> codec seems to be hard. Does anyone have any suggestions?
>>     
>
> Maybe try one of the daughtercards available for 6713 DSK:
>
>  
>
http://focus.ti.com/dsp/docs/dspsupporttoolssoftwareaut.tsp?sectionId=3&tabId=466&toolT
ypeId=48&familyId=132
>
> Note that "daughter cards" from Pentek, Innovative, Surf, Signatec, and a few
others
> are actually PMC or other form-factor modules that do not mate with DSK boards (have
> no idea how they got on this page, which says "...connect with TI DSP Starter Kits
> (DSKs)...").
>
> -Jeff
>

(You need to be a member of audiodsp -- send a blank email to audiodsp-subscribe@yahoogroups.com )