A mathematical method of generating thermal models for power devices

It is vital important for a designer to understand the thermal characteristics of a power device as the size of end-product shrinks while the power level increases. Although a variety of modeling tools have been developed for thermal simulation, it remains a major hurdle in performing accurate analysis of power semiconductors. This paper presents a mathematical method that generate Froster R-C (resistance-capacitance) model using the datasheet information published by manufacturer, which aims to perform an accurate and efficient estimation for the junction-to-case temperature of a power device under high power transient. Implementation of the model in a circuit simulator enables the thermal analysis of power semiconductors for any operating condition. An example of featuring a power MOSFET is presented in this paper to demonstrate the application of this method in thermal model generation.