Alexandre Guimar=E3es wrote...

>    No getting back to the SMPS. I will have an application where I will
>have to make a supply with 74 volts DC input and 24 v at 300 ma and 5 v =
at
>30 ma. I am thinking about using 2 of your 2 transistor designs modified=
 to
>the my specific needs. When I finish it I will let you and the list know=
 how
>it goes and what modifications are needed.

With those voltages and currents, why not use Russell's design to step
the 74 volts down to 24, then Roman's circuit to step the 24 volts down
to 5?  Russell's circuit is probably more suited to the high-voltage
part of this thing, especially if you need 300 milliamps out of it.

Dave

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