Connector, Cable Systems For AI Hardware Design

In this video, Samtec’s Ralph Page walks us through a live demonstration of a prototypical AI (artificial intelligence) hardware design. It shows PCB connectors and twinax cable systems with performance capabilities suitable for AI hardware applications.

It’s a configurable, next-generation, possibly GPU-based system that combines a cable mesh backplane, a rigid-style backplane, high-speed edge card connectors, and precision RF interconnects.

For example, this design could be based on the GenZ-PECFF form factor. It’s a scalable, 32 GT/s silicon test platform that incorporates up to eight riser cards that include PCI Express® 5.0, or even 6.0, interconnected with the Samtec Flyover® concept.

Both backplane and cable mesh systems are accepted PCI Express topologies.

Synopsys DesignWare® IP for PCI Express 5.0 at 32 GT/s with built-in eye capture capability generates 32 GT/s NRZ and routes it through RF cable to a Samtec 2.4 mm RF connector, then to a rigid backplane comprised of Samtec HSEC6 micro edge card connectors. Riser cards plug into the Samtec micro edge card connectors on one side, and Samtec AcceleRate® ARC6, ARF6 connector systems are on the other end.

The signals then transfer from card to card via two right angle Samtec high speed cable assemblies. These are AcceleRate right angle PCB interconnects, with Eye Speed® ultra-low skew twinax cable. We see several cable assembly lengths, from 2.5” up to 12”.

The signals travel through the second paddle board, through another HSEC6 edge card connector, and then out through another 2.4 mm RF connector.

The worst case is demonstrated, with the 32 GT/s signal transferring from the backplane, through the two riser cards placed furthest apart. This is over 12 inches apart.

The results are fantastic. 32 GT/s signal transferred with zero bit errors. The 12” AcceleRate cable connector assemblies are delivering zero errors with excellent eye results. Compare the 2.8 dB loss through 12” of cable with about 20 dB loss on a rigid PCB backplane of the same 12” length using standard FR-4, or 14 dB of loss on higher grade Megtron 6 materials.

This demonstration shows that Samtec Flyover technology and high-speed interconnect systems can effectively operate in 32 GT/s platforms that incorporate up to eight riser cards that include PCI Express 5.0 AI, ML usage models.