cant get output signal from DVDAC (12 bit)

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Anonymous
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Hi

   

I am trying to pass an audio signal as shown in the schematic but the part I have the problem is between the filter to DVDAC(12 bit)
unfortunately I can't make the DVDAC output any normal signal
all the other parts work good
also when I used VDAC8 it worked ok but i need 12 bit resolution from the filter.
(I use the opamp in order to get enough current for the speaker
did I place the capacitor for DVDAC on the right place

   


please help me with that
thanks

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Anonymous
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do you need all the project will work in 12 bits?what I am not sure the capacitor should be located there..maybe before the opamp,what about the main.c did you manage to read properly?

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Anonymous
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thanks

   

I had a working project with VDAC8 and I changed it to DVDAC because I want all the project to work with 12 bit resolution

   

I changed in the main.c but I think I have a configuration issue there(how to read in the right way 12 bits)

   

I didnt know about the capacitor because I have to use an opamp I tries before and after the opamp but didnt work

   

also I had a look at the example project but didn't have enough info

   

do you know someone that can  have a look and tell me what is no t defined well in the project  for 12 bits(main.c and schematics)?

   

attached again

   

thanks a lot

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ETRO_SSN583
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Yes, the cap should be at the output of the DVDAC. before OpAmp,

   

so add a pin to bring that connection out.

   

 

   

Also in your code you have the OpAmp_Start() commented out, so

   

that OpAmp is off ?

   

 

   

Considerations for analog routing -

   

 

   

    

   

          

   

http://www.cypress.com/?rID=39677     AN57821 - PSoC® 3, PSoC 4, and PSoC 5LP Mixed Signal Circuit Board Layout Considerations

   

http://www.cypress.com/?rID=40247     AN58827 - PSoC® 3 and PSoC 5LP Internal Analog Routing Considerations

   

http://www.cypress.com/?rID=39974     AN58304 - PSoC® 3 and PSoC 5LP – Pin Selection for Analog Designs

   

 

   

 

   

Regards, Dana.

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Anonymous
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Thanks a lot I will try it and let you know..

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ETRO_SSN583
Level 9
Level 9
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Note set OpAmp properties to high power.

   

 

   

Regards, Dana.

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Anonymous
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Hi Dana,

   

Thank a lot again !!

   

unfortunately I tried to take a pin out and to put a 10nF capacitor to grownd , I took off the comments from the Opamp as you said

   

but I still dont get the results

   

what do you think is the reason?

   

1.code( I added a comment to what I changed for DVDAC)

   

2.definition of components?(I need 10 K samples per secons and 12 bit resolution)( the DeltaSigma was defined to 12 and to 8 but with no success)

   

3. the kit?(It is new so I guess it is nor the problem)

   

4.pin assignments is not ok

   

 

   

attached the modified project kindly your help

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