Entropy as a wear out indicator: The resistor example

In this contribution we aim at proposing entropy measurements in resistive elements to characterize the induced damage due to current and Joule effect dissipation. 0.25 W off the shelf resistors are biased with constant voltage and pulsed voltage signals, leading to power dissipation in the range of 2 W - 5 W, to accelerate resistor failure. Entropy is inferred from injected power with respect to temperature evolution. Results show an entropy increase as a function of time, thus being possible to define threshold entropy prior to resistor failure. Entropy generation rate also shows a sudden increase in strongly damaged resistors.