On Wed, 11 Feb 1998 14:37:37 -0800, you wrote:

>For 3 VOLTS for the PIC I use an LM-317L 3 terminal adjustable regulator,
>which is good for about 100 milliamperes.   I use a 220 ohm resistor between
>the output terminal and the adjust terminal, and approx. 325 ohms from the
>adjust terminal to ground. Use a capacitor from output to ground - several
>microfarads tantalum will do.    If you want to adjust the voltage  +/- 10%,
>use 270 ohns in series with a 100 ohm trimpot, from the adjust terminal to
>ground.
>I have used 3 volts on my PICDEM-1 board and get good results with 3v with
>the PIC-16C71 chip.
>Emerson Hoyt, Hoyt Instrument Lab, Beaverton, Oregon.
The normal reason for using 3v is to save power - a regulator which
takes 5 times as much current as the PIC for the resistor chain alone
isn't exactly an optimal choice....!
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