I'm trying to modify Roman's 2-transistor SMPS circuit to make a 150 to 5
VDC converter and I can make it work but I am dissipating a lot of power in
the transistor base resistors.  I tried to find a high voltage PNP
Darlington to help with this but I have little luck finding one.  I did the
classic Google and datasheet searches but seems the highest I can find is
around 40V.  I really need one that is rated at least at 240 Volts or so.

I'm only looking at supplying a max of 100 mA.  Anybody know of a source
for a high voltage PNP Darlington that I could use in this application?
Anyone ever try a FET with Roman's SMPS???

Thanks.

Mark Peterson

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