DAC to PGA : Will interfacing be a problem?

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MuKa_284621
Level 3
Level 3

 Hello,

   

 

   

In one of my projects, I wanted to connect a DAC acting as a reference voltage source (Vref) directly to the Vref input of a PGA component.

   

 

   

I just wanted to know is that is a good idea in terms of interfacing the two components together since I didn't find much about the input resistance of the PGA.

   

 

   

The VDAC has a 4kOhm typical value for the 1.024V range, so the PGA has to be at least 10 times that to be considerable (I think).

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ETRO_SSN583
Level 9
Level 9
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The datasheet has the nominal value of the G setting R's for the PGA.

   

 

   

Computing Zin -

   

 

   

    

   

          

   

http://users.ece.gatech.edu/mleach/ece3050/notes/OpAmps/opampbw.pdf

   

 

   

http://www.colorado.edu/physics/phys3330/phys3330_sp12/phys3330_sp12/Lab_Manual_files/Exp_4_Spring12...

   

 

   

   

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