cloudhead

Right. This is why i am asking exactly about input of HV reg (high voltage low current). Seems to be perfect place for it. Its cheap, it relatively cold and small. Could be done with additional protection, to be even more failproof.

Thanks for info! IMHO the $5k DMM/voltmeter doesn't help much with this sort of measurements because self noise even best of them is more than 1 nV (in practice > 10 nV). The only solution could be to use some unknown to me LNA. Its good to know that this is possible. https://www.analog.com/media/en/technical-documentation/application-notes/an159fa.pdf https://www.analog.com/media/en/technical-documentation/application-notes/an83f.pdf Thank you very much for the answers! BTW do you see any reason not to replace huge input capacitors for the HV regulator with reasonable capacitance multiplier (e.g. 10u pre + 10u in cap.mult. + 10u post)?

Hi Kevin, Could you please provide description of your measurement setup? What kind of LNA could provide such low noise to not mask the claimed noise of this regulator? What was the bandwidth of this measurments?

Please try to update your LTSpice. It should be in your libs Sorry, for misinformation. Forgot to add it. Please rename to .asy and put it in the same directory as other files. power_nmos_heat.doc also make sure you have this setted to yours location

For those who might need LTSpice model for Cabon e.g. for debugging. Red LED is just some generic. Rename to .zip kgsshv_carbon_spice.doc

Is there any good subs for ksc2752?

Can you share more detailed schematic of latest revision, please?