Hi,
I build in LTspice some old power supply using LM723.
But this circuit start oscillate when entering constant current mode.
Someone has any idea how prevent this oscillation?
Your separate current limiting circuit is operating too fast for its loop gain. Slow it down with an RC somewhere in the feedback path or reduce its gain. The LM358 on output should not be operated at open loop gain. If you are trying to get an overcurrent latched shutdown then you need to add a latch with a manual reset Otherwise the circuit must operate in linear mode where the regulator output voltage is reduced until an equilibrium is reached at the desired maximum output current.
Used them many times, never had problem. You should be using the 100 pF comp cap to -inv input.
The only thing all the extra current limit circuitry will buy you is tighter current control over temp and maybe less voltage drop then the 0.6v for internal cutback NPN Vbe.
The op amps circuit add constant current mode. So power supply should act just like a constant current source.
CC mode triggers when the load current reach