Credo and Samtec teamed-up to to show an impressive 112 Gbps PAM4 long-reach cable demonstration at DesignCon 2018. In this video, Samtec’s Ralph Page and Credo’s Alex Narazi walk us through the demo and the results achieved.
Signal Path

Three ports of 112 Gbps PAM4 data are sources from the Credo 112 Gbps PAM4 CDRs. The signals are routed through RF jumpers to an SI characterization card for Samtec’s next-gen AcceleRatee® Cable Assemblies. One data path is a signal while the other two are aggressors.
The signal then passes through approximately 12″ (30.5cm) of Samtec Ultra-Low Skew Twinax cable within the Samtec AcceleRate Cable Assembly. That passes through a second AcceleRate Cable SI Evaluation card. Then, the signal path routes through the second set of high-performance RF jumpers to a second Credo 112 Gbps PAM4 CDR.
The channel output is displayed on monitors.
Results
The video shows 112 Gbps PAM4 transmission-side eye patterns and the receiver-end of the cable assembly. There is approximately 10 to 12 dB loss in both test PCBs. The low loss (0.33dB per inch) and ultra-low skew of Samtec’s AcceleRate Cable Assembly provides a clean eye diagram achieving a BER of approximately 5e-7
These results easily meet standards such as IEEE Std 802.3bs-2017. Flying signals over lossy PCBs with Samtec’s AcceleRate Cable rather than through them offers a better value and increased performance for next-gen system architectures.
AcceleRate Interconnect System
Samtec’s AcceleRate Cable Assembly is the slimmest in the industry with a 7.6 mm body width ideal for closer proximity to the IC. The high-density two-row design features 8 and 16 pair configurations on a 0.635 mm pitch for up to 92 pairs per square inch.
Rated to 56 Gbps PAM4, this assembly supports Samtec’s Flyover™ technology by flying signals over lossy PCB via ultra-low skew Twinax Eye Speed® cable. This proprietary co-extruded cable supports next-generation performance with extended reach and system flexibility. The ARC6 is the cable assembly, and ARF6 is the board level connector
For more information on this demo, contact signal integrity team at SIG@samtec.com. For more information about Accelerate high-speed cable assemblies, contact our technical experts at HDR@samtec.com.
Other links that may be of interest:
Related Links:
- Samtec Twinax Flyover Cable Technology
- Ultra-Low Skew Cable Technology
- FireFly™ Application Design Guide
- Flyover QSFP28 Cable Systems
- Flyover QSFP Application Design Guide
- High-Speed Cable Assembly Products
- Samtec Releases New High-Speed Cable Interconnect Solutions Guide
- TI and Samtec Demo 56 Gbps PAM4 Over Backplane At DesignCon 2018
- Samtec New Products At DesignCon 2018