Investigation of SPICE Models for Overvoltage Protection Devices With Respect to Fast Transients

Models of overvoltage protection devices such as voltage suppressor diodes (TVS) are available for the most part in circuit analyzer tools. During the course of investigating the simulation of such protection devices via LTspice in the context of fast transient phenomena some assumptions of those existing models can present problems. This is the case regarding the model of the junction capacitances, especially for the cutoff region when predicting the disturbances generated by those devises.