| Abstract |
In this paper a new circuit simulation model for the high power diode is derived, that accurately describes the dynamics of the excess charge in its low doped region. This excess charge is responsible for its dynamic characteristics, and is important in most applications. The model is based on the semiconductor equations in ambipolar form and the model parameters all have physical relevance. The approach is to divide the charge into a number of subregions and describe the distribution in each one with a second degree polynomial. At the boundaries between the subregions, the distribution and its derivative have to be continuous. To each subregion belongs a charge control equation which includes terms for recombination and net supply of charge from the "outside". Other important effects, such as recombination in the emitters and the influence of free holes in the space charge layer on the voltage during reverse recovery are also included. |
