A high accuracy power MOSFET SPICE behavioral macromodel including the device self-heating and safe operating area simulation

Abstract

The new analog behavioral modeling features of modern SPICE simulators were used to develop a high accuracy power MOSFET macromodel, that considers the electrothermal processes and simulates the device behavior beyond the safe operating area (SOA) limits. New static equations were implemented with "in-line equation" controlled sources, in order to accurately simulate the device on-state voltage and forward transconductance. The model gives a precise description of the parasitic interelectrode capacitances, that were piecewise-linear approximated with "look-up table" controlled sources. The SOA was simulated by including the device avalanche breakdown and snapback effect. The model's parameters extraction was greatly simplified and the resulting model is portable to all the modern SPICE simulators. The simulations performed for different types of commercial power MOSFETs proved an excellent agreement with the data-sheet characteristics, giving also a reasonable analysis time, with no convergence problems.