Microwave Journal

Transient EM/Circuit Co-Simulation Improves ESD Protection

September 14, 2021

Remcom has updated XFdtd® 3D EM Simulation Software with transient electromagnetic (EM)/circuit co-simulation for electrostatic discharge (ESD) testing, adding support for transient voltage suppressor (TVS) diodes and spark gaps. The new capability helps engineers reduce costly ESD testing of hardware prototypes and eliminate certification setbacks in their device designs.

XFdtd has several tools for simulating ESD testing that reveal components susceptible to ESD damage, thus optimizing ESD mitigation and preventing trial-and-error testing on a physical prototype. The updated software will import TVS diode netlist files and include the diode’s nonlinear behavior in a finite-difference time-domain simulation. TVS diodes are used to protect circuits from the surge voltages of an ESD event. They are commonly placed along input/output lines, audio hardware, human interface devices, power supplies and the RF front-end of an antenna. While widely used, TVS diodes have been challenging to simulate in full-wave EM and circuit solvers.

Remcom’s transient EM/circuit co-simulation combines a transient nonlinear circuit solver with a full-wave EM solver. To enhance accuracy, XFdtd simulates non-destructive testing using a virtual prototype of the physical layout of the TVS components, simultaneously capturing all EM phenomena from the 3D CAD geometry and the complex nonlinear behavior of the circuit model in a single time-domain simulation. Various diode placements can be simulated to optimize the circuit layout and increase the ESD protection of the final design. XFdtd overcomes the limitations of specialized solvers used individually, enabling engineers to analyze device protection measures more efficiently and effectively. By resolving ESD vulnerabilities before committing to prototype hardware, certification setbacks are avoided.

State College, Pa.