Repetitive pulse testing and modeling of a high power ceramic resistor

In an effort to understand the failure mechanisms of ceramic resistors when used above their stated limits, a series of pulsed load profiles were applied to an epoxy coated ceramic resistor. A dependent relationship between the pulsed load profiles and the temperature of the epoxy was shown through the series of experiments. From these experiments a safe operating range was found beyond the stated limits. The load profiles that cause failure are evaluated and compared to the results of a lumped element numerical model, which models the thermal characteristics of such a resistor under test and allows for the heating profiles during operation to be predicted.