112 Gbps PAM4
Keith Guetig, Samtec’s High Speed Product Manager, walks us through a Credo + Samtec 112 Gbps PAM4 high-speed cable demonstration. This demo, showcasing Samtec’s Flyover™ cable technology, was presented at OFC 2018 in San Diego, California.
Signal Path and Equipment
Two ports of 112 Gbps PAM4 data are sourced from the Credo CDRs. The signals route through RF jumpers to an SI characterization card for Samtec’s FQSFP-DD connector.
The signal then passes through approximately 12” (30.5 cm) of Samtec Ultra-Low Skew Twinax cable within the cable assembly, then it passes through a Samtec Accelerate® high speed cable assembly SI Evaluation card. Finally the signal path routes though a second set of RF jumpers, to a second Credo CDR.
At the end we see the channel output. As the GUI shows, we ran 112 Gbps PAM4 data at a pseudo-random bit sequencing of 31 at 2e-7. This is a great achievement for both the Credo silicon and for Samtec Ultra-Low Skew Twinax cable.
The results achieved from the combination of Credo’s 112 Gbps-PAM4 CDRs with Samtec’s FQSFP-DD and AcceleRate® Cable solutions provide an ideal proof-of-concept for long reach signals over cable. (Note this demo used Credo Firebird (Tx) and Pelican (Rx) chips).
This demonstration shows Samtec’s Flyover technology, which allows a cost effective, high-performance answer to the challenges of 56 Gbps bandwidth, and as we see here, 112 Gbps.
AcceleRate, FQSFP-DD Cable Assembly
The Samtec AcceleRate Cable assembly is the slimmest cable assembly in the industry, with a 7.6 mm body width, which is ideal for closer proximity to the IC.
It’s available in 8 and 16 pair configurations, with up to 92 pairs per square inch.
Samtec’s FQSFP-DD takes the flyover architecture concept to the QSFP-DD form factor.
For more information on this demo, contact signal integrity team at SIG@samtec.com. For more information about Accelerate and FQSFP-DD cable assemblies, contact our technical experts at HDR@samtec.com.
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