Discrete regulators with denoiser

[pbilous]

The higher voltage shouldn't be an issue. I'd have to test higher current configurations. I'll try to prepare a higher current testing setup.
This is just a sim but as a general example:

View attachment 1121362


It's at 36V/20A output. Seems it could be doable. I used some random high power MOSFET model just to see how it would behave.
Higher voltage should also work but at some point there's going to be heat buildup in certain parts of the circuit (clearly apart from the pass transistor). So might need to use lower current for the denoiser circuit, or upgrade the power rating of the BJTs.

edit: also in this configuration Q1 takes a big hit at startup with a high base current surge. A protection resistor will have to be added, output capacitance would have to be increased, C3's value lowered etc. It's just a general example only.

Seeing that -140dB line makes me happy

 

[pbilous]

I wonder if something like this mosfet will work - IRFB3607PBF ?

Is it possible to use two, or say four of those for current sharing and to better spread the heat dissipation?

 

[Trileru]

That's N-channel, might work for negative output version. Positive needs P-channel.
I don't think I am equipped to test such output powers. I might try with a few amps output.

 

[Trileru]

Tried that IRFB3607PBF MOSFET for the negative voltage output version. 36V/100A output, seems to work with two in parallel. But I'm not sure about how large the source resistors should be. Input capacitors would need a 30mOhm total ESR, or lower if the source is lower than 10mOhm.
I might have made a mistake, never tried this before. No way of making a board for that kind of output current, I wouldn't be able to test it.
Different MOSFETs might improve performance a bit.
I attached a screenshot for +/- versions.

 

[Trileru]

Not sure if the source resistors are needed, but the voltage source needs a bit of output impedance, 10-20mOhms, and even lower input cap ESR.