As many others before, I'm aiming to build my own simple CC CV lab bench PSU based on the LM317 regulator. Now, I've defined most of the circuitry, but I'm stuck with a particular design choice regarding the Adj pin of the LM317.
Since I wanted to use an Op Amp to drive the Adj pin, I wanted to know what are the pros and cons when:
using the output voltage of the Op Amp at the Adj pin as negative feedback
using the output-voltage regulated by the LM317 as negative feedback.
In my mind the latter would be able to account for the voltage reference fluctuations of the LM317, but I assume that on the other hand it might be somehow unstable. If this is the case, how can I compensate for these instabilities?
Added the schematic for the Adjust-Pin driven LM317 circuit