Measuring small temperature changes can be done with a Wheatstone bridge and a thermistor. A thermistor is an electrical component whose resistance changes with temperature.

A Wheatstone bridge is one of those handy circuits that has plenty of uses in both AC and DC measurements. We probably see them most often in a strain gauge.

Bridge circuits have long been popular for conditioning signals from resistive sensors. These circuits are sensitive to small changes in resistance, and they provide a differential output from a ...

The basic form has been extended to measure the integral of temperature × time above the pre-selected value by building the thermistor, the voltameter and a diode into a wheatstone bridge circuit.