Another thought...

You are switching the power line (Vcc) of the MAX, right ?
What about the !FORCEON and !FORCEOFF pins ? Could you
manage them from the PIC insted and leave Vcc connected
directly to the power supply ? It also have an "Auto
Shutdown" feature, but that might not be usable here.

Anyway, using the !FORCExxx pins seems to be the way this
chips was ment to be used...

Jan-Erik.

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