Padu wrote:
> 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.
>
> The main power source is a battery pack that supplies 12V. What I'm
> trying to decide is whether I design one extra daughterboard for
> voltage regulation or if I include voltage regulation in each one of
> the daughterboards. Here's what I see as advantages and disadvantes
> of each method, please critique.

I might put a decent buck regulator on the main board that produces about
5.5 volts, then distribute that to each daughter board.  Each board would
have its own LDO to make a nice clean 5V from the rough 5.5V in.  Check out
the Microchip MCP1700 LDOs, they are very nice chips if you can guarantee
the input won't exceed 6V.

The advantage of this scheme is that it's reasonably efficient, the
regulator on each board is simple, but each board still has its own clean 5V
bus.  If you need 3.3V somewhere, you can probably linearly regulate it from
the 5.5V assuming current draw isn't too high.


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