EPEPS 2020: San Jose, CA
Tutorial II
Printed Circuit Board Interconnect Modeling Demystified

Lambert (Bert) Simonovich, Lamsim Enterprises, Inc.

When trying to meet insertion loss budgets for the latest serial link standards, board designers are often overwhelmed when trying to choose appropriate differential pair geometries, board material and stackup. Part of the challenge is modeling transmission lines accurately. Many electronic design automation (EDA) tools include the latest and greatest models for conductor surface roughness and wide-band dielectric properties. But obtaining the right parameters to feed the models is always a challenge. So how do we get these parameters? One way is to use the design feedback method which involves designing, building and measuring a test coupon with the proposed geometry. After modeling and tuning various parameters to best fit measured data, material parameters are extracted then used in channel modeling software to design the final product. But for many small companies and signal integrity engineers, they have to come up with an answer sooner, rather than later. By using dielectric material properties, and copper foil roughness parameters from data sheets alone, a practical method of modeling high-speed printed circuit board (PCB) interconnect is presented and correlated to measured results.

At the end of the tutorial, the audience will learn:
  • How to apply my “Cannonball” model to determine roughness parameters for Huray conductor roughness model from data sheets alone
  • How to determine effective Dk due to roughness from data sheets alone
  • How to apply these parameters in popular field solvers
  • Impact of causal metal model to simulated results
  • Impact of Oxide/Oxide Alternative treatments on roughness, insertion loss and impedance
  • How to pull it all together and compare simulated transmission line interconnect models with case studies
Lambert (Bert) Simonovich graduated from Mohawk College of Applied Arts and Technology, Hamilton, Ontario Canada, as an Electronic Engineering Technologist. Over a 32-year career, working at Bell Northern Research/Nortel, in Ottawa, Canada, he helped pioneer several advanced technology solutions into products. He has held a variety of engineering, research and development positions, eventually specializing in high-speed signal integrity and backplane architectures. In 2009, he founded Lamsim Enterprises Inc., where he continues to provide innovative signal integrity and backplane solutions as a consultant. He has also authored and coauthored several award-winning publications posted on his web site. His current research interests include: high-speed signal integrity, modeling and characterization of high-speed serial link architectures.