Any comments on the circuit at http://www.nosreme.org/tmp/selfpwr.png?

The intention is to run a PIC-based circuit (16F628) from a 9V battery,
but reducing the power consumption to (virtually) zero when not in use.
I also want to be able to read the status of the push-to-make switch
while running.

The switch turns on the MOSFET via NPN Q2, and the PIC can then keep the
power on through Q1.  It can read the status of the switch on another
pin through R6.

This is a one-off hobby project, and I already have these parts around,
which is why I haven't just got a regulator with shutdown option.

I have seen Roman Black's circuit at
http://centauri.ezy.net.au/~fastvid/self_swi.htm, but as this circuit is
likely to be running for a couple of hours at a time, I'd rather not
have to sink 5-10ma the whole time.

Thanks,

Chris

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