Samtec BE71A Bulls Eye for 224 Gbps SerDes Test

Introduction : As the data center and telecommunications industries aggressively push networking speeds to 224 Gbps and begin charting the path toward 448 Gbps; hardware engineers face extreme signal integrity (SI) challenges. At these data rates, evaluating silicon and characterizing SerDes (Serializer/Deserializer) requires test fixtures capable of operating accurately at 71 GHz and beyond. Traditional test setups relying on bulky, single channel soldered coaxial connectors consume excessive printed circuit board (PCB) real estate, degrade signal quality and drive up testing costs. The Samtec BE71A Phase & Amplitude Test Assembly provides a high performance and high density alternative. This application note covers its features, key benefits and applications.

Key features Samtec BE71A

Following are main specifications of Samtec BE71A model.

• Available in different frequency ranges e.g. 40 GHz, 50 GHz, 70 GHz, 71 GHz and 90 GHz
• SerDes Characterization : 224 Gbps PAM4, 112 and 56 Gbps options available.
• End 2 connectors : 1.00 mm, 1.35, 1.85, 2.4 and 2.92 mm are available.
• Microstrip/CPW or stripline PCB transmission
• Visit www.samtec.com for more information.

Samtec BE71A Benefits

Following are some of the advantages of Samtec BE71A solution.

• Instead of soldering individual connectors, the BE71A utilizes a compression-mount block that mates directly to PCB pads
• At 224 Gbps, a single Unit Interval (UI) is less than 9 picoseconds wide. Any phase mismatch between test cables can instantly erode the margin of error. To combat this, the BE71A utilizes Samtec’s proprietary Nitrowave™ cable technology specifically LL071 cabling. Nitrowave is engineered to maintain exceptional phase and amplitude stability even when the cable is flexed, bent or subjected to temperature changes (-65°C to +125°C).
• To measure frequencies approaching 100 GHz, engineers are often forced to adopt 1.00 mm test equipment, which is notoriously expensive, fragile and difficult to torque correctly. The BE71A addresses this by bridging the high-density board interface to standard 1.85 mm connectors at the instrumentation end. The 1.85 mm interface is mechanically robust, widely supported by test equipment manufacturers, and fully capable of handling the 71 GHz bandwidth required for 224 Gbps PAM4, saving laboratories the immense capital expense of prematurely upgrading to 1.00 mm hardware.

Key Applications

The compact size and high SI performance of the BE71A make it ideal for following applications.

• SerDes Characterization: Validating next-generation network switch ASICs, PHYs and AI processors.
• Automated Test Equipment (ATE): The high density block can be integrated directly into the front panels of BERTs or custom test racks.
• Quantum Computing: Connecting dense arrays of cryogenic control lines where space is strictly limited and phase stability is critical.
• High Density Multi Port I/O: Any application requiring dense cable to board transitions without the signal degradation associated with traditional ganged connectors.

Summary

As the industry scales toward 224 Gbps and 448 Gbps, the interconnects used in the laboratory must not become the bottleneck. The Samtec BE71A Bulls Eye assembly provides a masterclass in high frequency test design. By combining a space saving solderless PCB interface, 0.5 ps phase matched Nitrowave cables and cost effective 1.85 mm instrumentation connections, it empowers engineers to accurately characterize next generation silicon while minimizing board space and equipment costs.