Thermal Impedance Matrix Characterization of Co-Packed Discrete IGBT and Diode

Abstract:
The thermal characterization of electronic pack-ages having multiple independent heat sources, such as an IGBT co-packed with a free-wheeling diode, is of crucial importance in the design of reliable and efficient power systems. The junc-tion-to-case thermal resistance RThetaJC for each thermal path starting from each junction must be determined. Moreover, since the dice are thermally coupled through the lead frame, cross-coupled thermal resistances cannot be neglected. In this paper, the TDIM – Thermal Dual Interface Measurement method – is applied together with the analysis of structure functions to obtain the thermal impedance matrix of a 120 A, 650 V IGBT co-packed with a free-wheeling diode.