Dwayne Reid wrote...

>PS: I think the name of Mr Woodward's article was: Low Cost Precision
>Thermometry.  Try doing a web search on that string.

I didn't get anything off google on that string, but Linear Technology
application note AN-45 has what I think is Jim Williams' original
circuit of the "delta-Vbe" thermometer, at:

http://www.linear-tech.com/pdf/an45.pdf

on page 7.  It has a pretty good explanation of the circuit's principle
of operation, and should be easily adaptable to run off a 5V supply for
input to a PIC's A/D converter.

Dave

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