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A G R E AT E R M E A S U R E O F C O N F I D E N C E is straightforward, but there are physical
limitations to this technique due to the finite
size of the sensor. In many cases, the sensor
itself would be larger than the junction to be
measured. This would add a large thermal
mass to the system, and additional error to
the measurement which would lessen the ac-
curacy of the measurement. Therefore, this
technique would not be very useful in most
applications.
A better technique is to employ the junc-
tion itself as a temperature sensor. With most
materials, there is a strong correlation be-
tween the forward voltage drop of a junction
and the temperature of that junction. The
Using Forward
point at which a junction becomes nonlin-
ear with respect to junction temperature is
dependent on the material of the junction as
Voltage to Measure
well as its design. It is safe to assume linear-
ity for most materials in normal operating
environments up to 80-100