Charged Board Model ESD Simulation for PCB Mounted MOS Transistors

In this paper, power MOS transistor behavior under charged board model (CBM) ESD impact is considered. The analysis of the MOSFET failure condition at the CBM ESD event is performed. The CBM equivalent circuit is proposed. The physical parameters of the PCB and device under test are replaced by the lumped RCL circuit. The MOSFET failure voltage calculation method is developed. This method is based on the transient analysis of the CBM ESD equivalent circuit with the general purpose open-source circuit simulator Qucs. This simplified method allows us to calculate CBM ESD voltage dangerous for the MOSFET with less than 20% error for some application cases (pins without ESD protection). CBM ESD tests are performed. Simulation and measurement results are in good match.