Diode Models

Although diode is not a field effect device, it is part of the parasitics associated with the field effect devices. Field effect devices have junction diodes which are not part of the intrinsic device but are part of the parasitic components which need to be included in the model. This chapter describes the diode model suitable fo this purpose. This model is simpler than the model implemented as a general diode model in many of the circuit simulation programs. The general diode model includes parasitic series resistance effects and reverse bias breakdown effects which are not modeled for the parasitic diodes. For normal device operation, the parasitic diodes are supposed to be reverse biased and their contribution to the device characteristics is normally negligible. Hence there is no need to use a complicated model.