Plugging a board into a live backplane, running 48V, where the board will
have a 3.3V always on DC/DC, and a main 12V DC/DC module.

Using a hotswap controller like the Supertex HV100 solves most the problems,
in that I will tie it to the 3.3V that has a on its rails a PIC, which then
actually turns on the 12V DC/DC unit.

So...being that there is really no load other than the front end filter caps
for the 12V DC/DC module, and it won't be turned on until the PIC is up and
running, does it make sense to have a hotswap controller there as well?

I was thinking more along the lines of using a FET and the PWM output to
ramp this 48V supply on...so to avoid a large inrush from the caps.  I'd
enable the 12V module and then ramp the gate voltage to soft start the main
supply.

comments?

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