Olin Lathrop wrote :

> Jan-Erik Soderholm XA (TN/PAC) wrote:
> > Or a N-chan FET on the "bottom" side ? Might be easier
> > to interface to the PIC ?
>
> That won't work because the voltage will then try to float up
> to 6V and end up conducting thru the protection diode.

Yes, that's a problem.

>
> > Or just using the *internal* FET of the PIC output pin and
> > connect the divider network directly to the pin ?
>
> I think you're missing that the PIC is running from a
> regulated supply and trying to measure the battery voltage
> about 2V above Vdd.

That is, "top" of the divider to Vbat, "middle" of the
divider to one PICpin and the "bottom" of the divider
to another PIC pin (as a on/off switch).  Wouldn't that
works just as well as an external N-fet (well, besides of
the problem above, of course...)

Best Regards
Jan-Erik.

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