> I am powering a device using the LM7805 (5V regulator).  I
> want to be able to turn the LM7805 on and off.

If it is just for the logical effect (not for power saving) you can just
short the 7805's output with a big transistor. I use TIP120 to do this
when I program PICs that need a Vpp-before-Vdd sequence.

Wouter van Ooijen

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Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products

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