Comparison of the Usefulness of Selected Thermo-sensitive Parameters of Power MOSFETs

The paper analyses the usefulness of selected thermo-sensitive parameters (TSP) in measuring thermal resistance of power MOS transistors. Three TSPs were considered: threshold voltage, voltage at the forward biased drain-substrate junction and voltage between the drain and the source of the transistor operating in the linear range. For each of the mentioned TSPs, thermometric characteristics were measured at selected current values. The linear range of each of the measured characteristics was discussed. An analysis of the measurement error of thermal resistance of a selected power MOS transistor was carried out using each of the considered TSPs. The results of thermal resistance measurements performed using the considered TSPs and a thermoresistor were compared and discussed.