This video shows how Samtec Flyover® twinax high speed cable assemblies extend signal reach and density, allowing designers to achieve 112 Gbps PAM4 performance in AI system hardware architectures. Matt Burns, Technical Marketing Manager at Samtec, recorded this video during the AI Hardware Summit, at the Computer History Museum in Mountain View, CA.
The Signal Path
The demo is driven by a Xilinx® Versal™ Premium GTM transceiver, which allows vendors to position their network systems for 800 G performance and beyond. The Xilinx GTM transceiver generates two lanes of 31-bit, PRBS data at 112 Gbps PAM4 data rates.
Signals travel from the Xilinx ACAP through about 2” of trace in the Isola Itera MT40 test board, to a Samtec Bulls Eye® connector, a BE70A, a 70 GHz high-performance test system.
The signal travels from the BE70A, through several inches of low-loss microwave cable, and is terminated to Samtec precision 1.85 mm compression mount jacks, which are mounted on a Samtec SI Evaluation Board.
The signals travel through another 2” of PCB trace to the solder ball termination of a Samtec NovaRay® high-density board-level connector. A NovaRay cable assembly mates with the board level connector, and carries the signal through 6” of 34 AWG Eye Speed® ultra-low skew twinax cable to the panel mount interface.
The fully shielded NovaRay I/O cable assembly plugs into the panel and moves the signal through 1.5 meters of 28 AWG Eye Speed ultra-low skew twinax cable.
The signal returns back through the second panel, to another NovaRay cable assembly, and back to a second SI Evaluation board. The data then travels through about 2” of pcb trace to another 1.85 mm precision RF connector, through another several more inches of low-loss microwave cable, to the Bulls Eye BE70A, and finally returning back to the Xilinx Versal Premium ACAP.
Performance
Looking at the Xilinx Vivado analysis tool, we see outstanding results.
As to the overall system performance, the slicer eye patterns are wide-open. We also have a pre-FEC BER of 1e-7, with zero errors post-FEC for the entire system. That’s 1e-7 over a 1.5 meter signal path that exceeds -40 dBs of loss. Over that entire signal path, the total loss attributed to the Samtec connectors and cable assemblies is less than -32 dB.
Samtec Flyover High Speed Cable Assemblies
Samtec Flyover solutions allow designers to extend the signal reach and density by routing signals via ultra-low skew twinax cable instead of lossy PCBs.
Other 112 Gbps PAM4 product demonstrations that might be of interest include …
- AcceleRate HP, 0.635 mm pitch high-density board-to-board system
- NovaRay ultra high-density board-to-board system
If you have questions about this demo, email us at SIG@samtec.com.
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