Isolated Feedback Circuit

[mp145002]

TEA19361T, what does this part of the circuit do? Obviously the optocoupler is feeding back the output with isolation, but how do the cap and thyristor affect this circuit?

[guoweisun]

Hi

This is a output voltage/current feedback circuit.

TL431 as a controllable precision voltage regulator,Capacitor as compensation circuit of TL431.