Abstract: According to the physical mechanics of single event upset (SEU),a two-dimensional simulation based on 0.35 μm PDSOI MOSFET explored by the Institute of Microelectronics of Chinese Academy of Sciences,has been done to assist to analysis the transit current induced by ion striking,for the purpose of citifying the electrical behaviors.The analysis result shows that there have two discharging phases during SEU,one is the excess electrons diffusion and drift current forming the prompt current;then the parasitic bipolar of PDSOI and the excess holes forming the long discharging current "tail".Combining with the fundamental physical mechanism,a mathematic model is proposed,providing with a one-dimensional analytical solution.A simple sub circuit model is necessary to characterize the extra longer delay part.Focusing on discussion of the sensitive parameter of SEU,this paper describes explicitly on the parameter extraction.An inverter is used as an example to compare the result between SPICE and TCAD simulation with the transient current,the collected charge of output node,and the LET threshold,which prove that the SEU SPICE model is reasonable and accurate to predict SEU effect.