分析传导EMI的功率MOSFET建模

Modeling of power MOSFET for conducting EMI analysis

基于集总电荷原理,分析了功率垂直双扩散MOS(VDMOS)开关过程各阶段极间电容CGS和CGD的变化,建立了连续的CGS和CGD的模型,利用产品数据手册的数据,采用曲线拟合技术可以提取模型方程中所有未知参数.在Saber仿真软件中,利用现有的LDMOS模型为核心,构筑功率VDMOS的子电路模型,作为精确的瞬态和传导电磁干扰(ElectromagneticInterference,EMI)仿真使用.最后的开关实验和仿真结果的比较证明了该模型的准确性和有效性.

Based on the theory of lump charge, the change of CGS and CGD  of VDMOS during the switching transition is analysed. The models of continuous C GS and C GD are developed. All model parameters can be extracted by a curvefittin g appro ach by comparing the model equations with some characteristic curves obtained fr om prod uction datasheet. In software package Saber, the subcircuit model of VDMOS at t he core of LDMOS is built up to get an accurate transient and conduct EMI(Elect romagnetic Interference) simulation. In the end, the comparison between the experimental and simulation result proved the validity and accuracy of the model. 