Modeling of the Saturation Characteristics of High Voltage Transistors

The conventional Ebers-Moll model does not provide an accurate representation of the saturation region characteristics for transistors with a high resistivity collector region. Accurate one-dimensional calculations of device characteristics indicate that the size of the effective collector resistance is modulated at high currents by the extension of the neutral base into the collector region. Based on this analysis, a non-linear collector resistance is added to the Ebers-Moll equivalent circuit model to provide a more accurate representation of the characteristics in the saturation region.