Component Model Calibration Using Transient Thermal Test Methods and Multiple Measurement Setups

Fine-tuning of finite-element thermal models to measurement data is presented, with the goal to obtain one thermal model that can accurately predict thermal response of a discrete power MOSFET in very different cooling scenarios. In particular heat paths through the plastic mold and through pins are considered in addition to the more widely studied main path through the thermal slug (mounting base). Different heat paths are activated during transient thermal measurements in dedicated test setups. Accurate 3D model geometry is obtained by means of simple reverse engineering of component dimensions. Manual tuning of material property values is the final step to obtain a detailed finite-element model which reproduces accurately the experimental results. This involves an iterative process, where material data is successively refined to reduce the mismatch of measured and simulated thermal impedance curves and structure functions.