High voltage power supply module

[jan.didden]

The current in J2 directly sets Vo, so if there is any drift there the Vo moves around. What you circuit does is keep the voltage between Vo and the top of J2 constant. That's not what you want.

Jan

 

[jan.didden]

View attachment 673980

My only concerns is that it uses feedback and I am not sure how it can impact the sound.

Alternatively I will use this:

View attachment 673981

I don't think this uses feedback; it is an emitter follower (also sometimes called capacitance multiplier) and not a regulator as their is no feedback from the output to stabilize it.

Jan

 

[jan.didden]

in the meanwhile...

I have replaced BJT with MOSFET, the output impedance is really small, I have replaced 2sk170BL with 2sk117GR (Idss around 4mA), the output voltage drift is much smaller.


I can't see any difference in output voltage with my voltage meter when I add 22.4k load, 13.4mA, 4W

5 milliohm with 13.4mA is about 70uV. You probably can't see that on your DMM ...

Jan

 

[ripson]

> 5 milliohm with 13.4mA is about 70uV. You probably can't see that on your DMM ...


5mOhm comes from the simulation, not measurement, it is what I said: it's so small so I can't see the difference in the voltage meter and thank you for the input I am familiar with Ohm's law what I am not sure is if replacing the bjt with mosfet here like that is a good approach