>There are a few LEDs that might need to be driven directly by PIC pins -
>such as in item (1) in Alan's message.  Run them at 4 or 5 mA and add that
>current to the 5V supply.  They don't need to be blinding - just
>visible.  The cheap T1 LEDs I am currently using are nice and bright at 4
mA.

ha ha. I know this too - I currently have a project where I am running a
bunch of high efficiency LED's direct from pins, with 100 ohm resistors. At
power on I set these to light up, and then extinguish as the initialisation
proceeds through the relevant parts. When you push reset it is quite
blinding :))

I'll be leaving them with 100 ohm resistors though, as they are interrupt
event indicators, so in normal operation they have very short on times, and
the 100 ohm seems to work out about right for this.

>As I see it, the power-hungry devices are the LEDs.  All the other stuff
>should consume less than 30 mA or so - that includes all 3 PICs, the
>op-amps, a LCD display.  Heck - even a 78L05 would probably work just fine
>if it weren't for the LEDs.

Yeah that does seem to be the way of it. I plan to run the LED's from
ULN2003 drivers anyway, so maybe a low power linear is really worth looking
at. Will check it out, and see.

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