The high-speed SI simulation usually takes a lot of lead time in PCB design projects, especially when it requires optimization to meet customer’s targets, there may need a lot of optimization rounds. And it’s also rather difficult to optimize the TDR, IL/RL to meet targets when there are lots of vias in the whole signal trace, even for experienced simulation engineers.Cadence have released a new simulation tool, Optimality, based on their existed 3D simulation tool called Clarity 3D workbench, which can achieve auto-optimization by parameter scanning and distribution calculation technology. Teradyne CHDC HW team have tested & verified whether this tool can apply to simulation projects or not, and how much improvement it can bring, and finally delivered high-speed simulation projects with this tool.In the tests and real projects, we found out Optimality can be very helpful in SI optimization, especially for all kinds of via optimization. In the projects supported by Cadence China MSA Service AE Team, max impedance in TDR have been improved 12.2~23.4ohm by using optimality, and RL improved 8.9dB (up to 120Gbps).By comparing between Clarity 3D workbench (optimality) results and VNA measurement, we decided that Optimality also have a very good accuracy. The optimality is very reliable.With this new tool, simulation engineer with/without experience can workout an optimization plan in one single night. It can save ~50% of simulation optimization time for strict spec project.