Abstract: A system for a power switch of a multiphase power converter coupled to an inductive load including a test controller, a voltage sampling circuit, a processing circuit, and a converter. A test pulse is applied to power switches of the converter to generate a test current through the inductive load, which forward biases a body diode of a power switch during a freewheel portion after the test pulse is completed. The voltage across the body diode is sampled during the freewheel portion, and the voltage samples are converted to a voltage value and a slope value. The voltage and slope values are converted to an estimated temperature value based on a characterization of the inductive load and the body diode. The conversion may be performed by a lookup table that stores an estimated temperature value for each unique combination of the voltage and slope values.