> 
> 
> This is probably a very basic question, but it is troubling me.
> 
> In my robot's design, I have a couple of daughterboards 
> running PICs (or maybe other uC's). I want to design a 
> circuit for supplying power to the daugherboards.
> 

Go with a power bus and re-regulate on each daughter card.  Consider
using DC/DC converters to reduce your losses to heat.  Somewhat more
expensive than a pile of 7805's but you might be happier in the long
run.  And you get to learn something too...  There is a 12V to 5V low
current, 2 transistor switcher design floating around.  Try searching
the piclist, I think it was something Roman Black did or improved or
contributed to.  Also I seem to Russell McMahon has had some posts about
cheap switcher designs.

Rob
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