ADP7159..ADM7155 REF_SENSE pin

Question

Is ADP7159 (or ADP7157, .. ADM715*) REF_SENSE pin driven by external DAC acceptable? 
 I wanto control the voltage with a SPI/DAC. 
 like https://ez.analog.com/power/f/q-a/100035/lt3090-output-voltage-controlled-by-dac

Errgy · Accepted Answer

Hi, 
 Controlling the output of ADP715x and ADM715x linear regulators using an external DAC is possible. You can control the output voltage to your desired value by adding/subtracting a margining current (I MARGIN ) at the REF_SENSE pin. 
 V OUT = V REF_SENSE + V R_TOP &plusmn; ∆V MARGIN 
 Since V REF_SENSE is constant, the change in output voltage (∆V MARGIN ) is dependent in I MARGIN and R TOP . 
 ∆V MARGIN = I MARGIN x R TOP 
 
 Below are some related readings regarding this method. 
 https://www.analog.com/en/technical-articles/voltage-margining-made-easy.html 
 https://www.analog.com/media/en/technical-documentation/data-sheets/LTC7106-1.pdf 
 https://www.analog.com/media/en/technical-documentation/data-sheets/292012fa.pdf 
 
 Regards, Errgy

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ADP7159..ADM7155 REF_SENSE pin

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