Recently, Cadence released its Clarity 3D Transient Solver for EMI simulation. I caught up with Brad Griffin, product management group director for multi-physics system analysis in the Custom IC & PCB Group at Cadence to follow up for some more details.
SIJ: What were the customer pain points that led you to develop the Clarity 3D Transient Solver?
Brad Griffin (BG): The Clarity 3D Transient Solver addresses the pain point of simulation capacity. Simulating full systems for EMI compliance is a big simulation job. Most experienced EMI engineers will not undertake this effort for fear that the tools are not up to the task. The Clarity 3D Transient Solver allows EMI engineers to make intelligent decisions without having to build a prototype and take physical measurements in a test chamber. Because of our massively parallel matrix solver, as well as GPU support, we can spread the simulation to dozens if not hundreds of processing cores. In addition, our solution is very memory friendly, so there is no need to have machines with terabytes of memory to ensure the simulation calculations can be performed. The combination of memory efficiency and scalable multi-core calculations enables overall system simulation to be performed in a reasonable period of time with reasonable computational hardware expense.
SIJ: How does it compare to the solution you offered this sector before?
BG:Our previous offerings are very good at looking at an individual PCB or IC package and guiding customers to areas where EMI can be reduced. The work flow has been to find as many problems as possible during design, fix those problems, and then build a prototype and test. Now we can simulate the full system and emulate the tests that take place with a prototype. This reduces re-spins and accelerates time to market.
SIJ: Your product aims to eliminate time testing in anechoic test chambers. What was your process for simulating these environments? What were the challenges your designers had to overcome to make the Clarity 3D Transient Solver able to achieve this?
BG:The Clarity 3D Transient Solver is a blend of technologies. Cadence had a finite-difference time-domain (FDTD) solver that was beta tested with positive simulation results, but the performance of the solver was similar to technology already available. We went back to R&D and asked if they could improve the performance while maintaining accurate simulation results. When the massively parallel matrix solver proven in both the Cadence Voltus IC Power Integrity Solution and Clarity 3D Solver was applied to the FDTD solver, we now had technology that we believed would change the game in EMI simulation.
SIJ: How do your customers validate their simulations? Any data you can share here?
BG: Most customer choose to run the Clarity 3D Transient Solver on a design that has reached the prototype stage and has been through testing in a chamber. The resulting design data is compiled into a virtual system, and the simulation results are compared to the results in the physical measurement. At this point, we have not published results of any of these comparisons. Some customer presentations are planned at events in the upcoming year. One exciting case we collaborated on was when the Clarity 3D Transient Solver was used to optimize the number of holes in a metal chassis. The holes existed to provide thermal relief, but they obviously also allow for more emissions from the PCB inside. By running several different scenarios, we were able to find a balance where EMI compliance could be met without disturbing the thermal integrity of the design.
SIJ: What other Cadence products are needed to perform this system analysis?
BG: To perform system analysis, the Clarity 3D Transient Solver requires the design data that composes the system, which may be a mixture of mechanical design and electrical design tools. Importing this data into the Clarity 3D Transient Solver is straightforward, especially when the ECAD data comes from tools such as Cadence Allegro technology or the Virtuoso environment. The Clarity 3D Solver, our finite element method (FEM) tool, complements the flow nicely with near-field emission calculations. In addition, the Cadence Celsius Thermal Solver complements the flow nicely to optimize system thermal and system EMI.
SIJ: What size projects is this product optimized for? For instance, you say “designing systems for 5G, automotive, high-performance computing (HPC), and machine learning (ML) applications with test-measurement accuracy” but specifically what types/size of products is this appropriate for?
BG: The larger the system, the more likely the Clarity 3D Transient Solver will provide a unique solution in that the capacity to simulate is available given enough computing resources. That being said, smaller systems with tight design cycles will also benefit from the tool since products can make it to market faster. Essentially any system that faces time-to-market pressure is a good candidate for the Clarity 3D Transient Solver to accelerate the EMI compliance testing portion of the product development schedule.
Brad Griffin is a product management group director for multi-physics system analysis in the Custom IC & PCB Group at Cadence. He has more than 25 years of experience in EDA technologies that enable the design and analysis of IC packaging and PCB systems. Griffin is a graduate of Arizona State University.