[sdiy] 1k tempco's in EU

[Ian Fritz]

At 05:31 AM 12/6/2006, Paul Perry wrote:
>Strangely enough, the tempco of copper wire is about what is wanted -
>4010ppm approx
>per degC

As mentioned on my tempco theory page, the theory of metals shows that all 
metals have resistance that changes linearly with temperature at high 
enough temperature.  I have a cool plot of about 20 metals lying on a 
universal curve (with appropriate variable scaling) that I found in a 
textbook some years ago.  To get the PTAT required for a tempco all you 
have to do is make sure the linear response goes through the origin.  You 
can do this with proper alloying or by building my dial-a-tempco circuit.

   Ian