The description of thermal non-uniformity in large area power MOSFETs requires the modeling of a thermal network to account for the thermal interaction between adjacent devices. In this work we propose a methodology to derive an equivalent thermal network which is able to predict the thermal transient as a function of the longitudinal distance from the heat source. The thermal resistances and capacitances are calculated by assuming a cylindrical propagation of the heat. Electro-thermal numerical simulations are performed in order to study the heat propagation inside the device and to verify the accuracy of the proposed model. (C) 2013 Elsevier Ltd. All rights reserved.