> Why can't the boost be driven off of an IO pin?  Is there a
> current problem?

One pin on its own would struggle to get 25mA (and it's at the
limit of spec anyway)

Also, I wrote :

"If the initial charge was to a little over 5.12V, the actual voltage
would have dropped to 5.12V at the time of acquisition, making
calcs a little easier and no fractions of bits to help results"

I'm used to setting, where possible, sensor and PIC Vccs in an
integeric (new word ?) relationship. Ultimately though the sensor
output and what it means is interpretation, no matter what maths
you use in the PIC. If the PIC Vcc can be matched to the range
of the sensor to make life easier, then all the better

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