Signal and Power Integrity (PCB/IC Packaging) Blogs

Accurate 3D EM simulation is increasingly necessary as data rates increase. For example, last year Cadence announced IP for 112G long-reach SerDes. The IP lives on a 7nm chip, which is a reasonably well-controlled environment. But think what the signal has to go through to actually work. It starts in the on-chip IP, goes through the package, onto a board, through a connector, into a backplane, a second connector, a second board, another package, and into the receiver on a different chip. Surprisingly, we can reduce all of this to a single impulse response to do signal integrity, but for that impulse response to be accurate, all of the structures of the packages, PCB traces, connectors, and cables need to be accurately modeled. Connectors, in particular, are highly complex mechanical structures.

Figure1: Global model extraction results using traditional Model Segmentation Approach

For this type of high-speed communication channel, there is no margin for error and true 3D analysis is required. But 3D modeling tools have not been keeping pace with design team requirements. Designers have been forced to use "pseudo-3D" which only has a chance of being close to accurate in the hands of a true expert. All analysis tools in EDA start off as analysis-only point tools, but what design teams really require is that the analysis is integrated with the implementation.

Figure2: Clarity is improving the performance linearly with the number of CPUs

Cadence^® Clarity 3D Solver has a next-generation true 3D solution delivering:

• Gold-standard accuracy
• World-class parallelization technology
• Up to 10X performance increase
• Integration with Cadence tools
• Availability through the Cadence CloudBurst platform

Figure3: Comparison: Traditional Flow vs. Clarity 3D Solver Flow

Socionext America faced a challenging problem—reducing the time and iterations required to perform electromagnetic analysis on the 56G PAM-4 nets in a new package design. Traditional approaches were cumbersome and time consuming, so they turned to the Cadence Clarity 3D Solver and cut the analysis time by 7X.

In this year’s CDNLive San Jose (CDNLive2019), Dan Lambalot, the director of engineering at Socionext America shared their experience in leveraging Clarity 3D Solver to accelerate package design with correlated accuracy. For the details of Socionext’s success, visit here.

Team Sigrity

space

Further Reading

• Blog: Bringing Clarity to System Analysis
• Product Page: Clarity 3D Solver
• Blog: How to Model and Simulate 112Gbps PAM4 SerDes Using IBIS-AMI
• Blog: The World's First Working 7nm 112G Long Reach SerDes Silicon