schematic:
this design is to build a wide range voltage/current PS.
I don't know why the original designer chose the 2 ohm, 10 ohm, Darlington 100k ohm (what's this?), 1k ohm shunt ( just = 0.7 volt / leakage current from Q1 Emitter ), 330k ohm, and 100 ohm in seriese with LM317.
My only understanding is: since the input is high (230 volt DC rms or 230/0.707 volt DC peak), both Q1 & Q2 are in active mode.
there is no bleed resistor, why the designer put 2 ohm, 10 ohm serialed capacitors? try to filter noise as well as regulate DC voltage? how to choose them?
what does the 100 ohm use for ? to compensate phase???
This circuits will be operated < 25 mA, that's fine for single MPS U10, why use Darlington pair?
totally lost.
Thanks for your help.