temperature compensation.

[Rene Schmitz]

At 10:50 02.08.99 -0500, Grant Richter wrote:
>You can also then use the 3500ppm tempcos that are (were?)
>in the Farnell catalog. I bought 25 of these by mistake (at $3.25 ea).
>This is a 1K 3500ppm POSITIVE tempco. You can put them in
>the high side and use a 18 ohm on the low side. You will have
>to buffer them with an op-amp of course.

Now, this puzzles me. 
The resistor needs have a *postitive* tempco needs when in the lower leg of
the divider, and a *negative* tempco when in the upper leg. We want a T
proportionality for the input voltage, to cancel the 1/T proportionality in
the convertor. 
Or am I wrong?!

Bye
 René

             ,   : (uzs159 at uni-bonn.de)
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