Simple Current Limiter (LM317)

[BillTodd]

I am intrested to know what caps to use to stop or limit any voltage noise.

Apart from the main PSU smoothing capacitor there's not a lot you can filter (since the o/p voltage will/must vary greatly).

You'll probably need to add reverse protection diodes across the current limiters.

[Mad Professor]

I have just scoped my power supply and it's quite clean there is only a 85.54mv deviation at 36.53volts.



As soon as you connect the LM317HV and a stepper motor you can see a saw wave on the power to the LM317HV.




This reading is taken from the power into the LM317, not the output.

Will adding reverse protection diodes across the current limiters cancel this out.

Thanks for your time.