Multiphysics Approach Using Computational Fluid Dynamics for Signal Integrity Analysis in High Speed Serial Links

Historically, signal integrity (SI) modeling and analysis was performed standalone without considering non-electrical aspects of the design. Going forward, this approach may not be viable to model high-speed serial links. Increased demand for higher CPU core count is resulting in higher wattage CPUs. This in-turn is increasing the number of phases of voltage regulator module (VRM) driving higher thermal footprint for the design. Increase in temperature impacts high-speed interconnect performance adversely. Modeling interconnects for worst-case operating temperature can be unrealistic and could lead to over-design of a channel. In this paper, a Multiphysics approach is proposed to model next generation high-speed interconnects. Computational fluid dynamics (CFD) is used to determine the temperature gradient in the channel and thermo-electrical co-analysis is proposed to accurately predict the interconnect signal integrity (SI) characteristics. A realistic test case is used to demonstrate the importance of proposed Multiphysics co-analysis for different data rates.