文档介绍：Optimization of a High Speed PCB Signal Launch Authored by: Suresh Subramaniam (Xilinx) Martin Vogel (Ansoft) Ansoft 2003 / Global Seminars: Delivering Performance Presentation #12 Motivation for Work “How can Xilinx help its customers make their signal launches more transparent?” Agenda w Description of Device w Fixed Parameters w Variable Parameters w Simulation Set-Up w Optimized Design w Sensitivity Analysis w What-If Analysis w Conclusions PCB Launch Fixed Elements • Board manufacturing technology Coaxial cable • Connector geometry • Board stack-up • Signal layer on PCB Signal via (radius only) Ground vias Connect to all ground planes, not to power planes. Variable Elements Distance from ground via to signal via Radius of ground via Variable Elements Length of via stub Variable Elements Radius of antipad under trace Variable Elements Radius of other antipads Variable Elements Radius of signal pad