Three-Dimensional Electromagnetic and Circuit Cosimulation for Printed Circuit Boards Mounted Linear and Non-Linear Electric Elements

Currently, there is no established method for simulating the excessive response of printed circuit boards (PCBs) with nonlinear circuit elements through electromagnetic field simulation. On the other hand, the threat of intentional electromagnetic interference (IEMI) is increasing, making it urgent to establish simulation techniques for designing countermeasures. In this paper, we performed simulations of PCBs with linear and nonlinear circuit elements by integrating the FiniteDifference Time-Domain (FDTD) method with SPICE in a co-simulation approach. Furthermore, this study constructed a measurement system to evaluate the accuracy of the simulation results. It was confirmed that the simulation reproduced the measurement results with an error of a few dB. It is possible to handle nonlinear elements through the co-simulation that integrates the FDTD method and SPICE. Therefore, this paper concludes that this co-simulation can be utilized in the design of IEMI countermeasures.