Simulation and modeling-a CAD model for the BJT with self heating

Abstract

A Gummel-Poon model that accounts for self heating in the bipolar-junction (BJT) transistor is presented. The model uses a simple but flexible RC analog circuit for thermal effects. Junction temperature as a voltage is a byproduct of the modeling approach. In contrast to the standard model, this model does not require changes in BJT parameters in order to track circuit changes that affect BJT dissipated power. Although not presented here, transient behavior due to self heating and thermal capacitance has been tested, and it is also correctly predicted by this model.