Sep Seyedi wrote:

>I am using the 12c509 on a really tiny robot. And I would like to power the
>PIC up with the smallest battery out there for about an hour.
>
...
>Also, ideas/routines on the usage of the PIC to allow it to be as efficient
>as possible (I think using sleep command???)
>


Sep:
        I've played with the '508s quite a bit, and typically measure about
0.6mA total to the chip when on it's internal RC. Pretty well any battery
ever made will last an hour at this rate. If you use the sleep mode,
current will drop to almost immeasureable levels.
        What you really have to look out for is the current drawn by the
pullups and your external circuitry. These can really add up in a hurry
(have you looked into interfacing to VMOS power transistors rather than
bipolars?).


        Jim Nagy
        Elm Electronics
  ICs for Experimenters
http://www.elmelectronics.com/