BillW wrote:
>I wanted to sense battery voltage, in a circuit run directly from the
>battery, by ...
>1) use IO pin(s) to run voltage doubler
>2) voltage doubler goes to zener on Vref
>
>This would let a pic running from (say) a Li-Ion batter (3 to 4.1V useful
>range, I'd guess) sense the battery voltage on an absolute basis, at the
>equivilent of very low dropout voltages...
>
>Does that sound reasonable?
>

Hi BillW, forget the voltage doubler, just use a 2.5v ref diode
run straight off the I/O pin.

- danM

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