hi group..me again

I want to bounce something off the members.


So I have a board that I designed with a 10K
thermistor, but its feeding a 3.3V micro (and that is fixed...cant change t=
his
part).=A0 They have come back and asked for
a better resolution.=A0=20
=A0
Now a thermistor, it simply generates a voltage
as a divider with a source impedance of course. =A0As the temperature chang=
es, the voltage that
is
generated across it changes, and the resolution
of what you can measure is going to be dependent on the source voltage as w=
ell
as the ADC resolution.
=A0
So the ONLY way to get better resolution is to
be able to increase the source voltage from 3.3V to 5V or use a higher
resolution ADC.=A0 Now for either case, the
micro thats reading this is 3.3V, so using 5V is out of the question.
=A0
Sorta thinking....using a PIC running at 5V to
read the thermistor, and then either using a PWM output (with RC filter) to=
 regenerate
a voltage of controlled steps over the temperature range they want to measu=
re
(pretty sure its 0 to 100F) for the ADC in their part to measure.
=A0
Any=A0 other possible clever ideas?


--=20
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