Frequency Based Method Investigation to Extract an ESD Protection Dynamic SPICE Model From TLP Measurement

Abstract

In order to ensure reliability of systems early in the design phase, it is becoming crucial to have models able to predict the behaviors of systems exposed to electrostatic discharge (ESD). This is an increased necessity since the number of embedded electronic products is growing and since they are involved in applications where people's safety is a requirement. Until now, quasi-static models of protection devices have succeeded in providing fairly good results in failure predictions (mainly hard failures). Today, the increased frequency range of the devices requires dynamic models able to reproduce its transient behavior. In this article, we investigate if conventional modeling methods of linear devices, generally used in frequency domain, could be used to get an equivalent frequency model for ESD protection devices, which exhibit a nonlinear behavior. A methodology to extract an ESD protection SPICE model from transmission line pulse (TLP) measurements to address transient and frequency simulation is proposed and detailed. We will demonstrate that in well-defined conditions, such frequency models can give accurate results to predict overshoots related to protection devices triggering delays. Validation of the models is performed under TLP and human metal model conditions on three off-the-shelf devices.