A dynamic thermo-feedback model for bipolar transistor

A compact bipolar transistor model is proposed to analyze the thermal effect on the device operations. The rise of working temperature is modeled as a feedback voltage to modify the operation of the transistor. Basic structure of the model is composed of two transistors, one for base-collector junction characterization, the other for base-emitter characterization. The principle is described and the model is successfully implemented on SPICE3. DC, AC and transient analyses are all included. Excellent agreement between the model and the experimental data of dynamic output characteristics of a microwave power transistor justifies the model.