As another year dawns, the demand for data remains insatiable.
The number crunching of Big Data requires larger and faster supercomputers to analyze immeasurable data sets. New server architectures leverage hardware accelerators – in FPGAs or via expansion cards – to offload system processing.
The growth of the IoT gives rise to data acquisition systems aggregating GBs of data. High-speed test and measurement equipment emulate signal traffic found in next generation routers, switches and data center interconnect.
At the physical layer inside these and other applications, 25 Gbps+ data rates are standard. The system CPUs, FPGAs, ASICs and ASSPs leverage transceivers for high-speed serial channel connectivity.
Routing 25 Gbps+ data rates on PCBs remains a challenge due to signal integrity issues associated with long trace lengths. System architects and PCBs designers are adopting various fiber optic solutions to route signals over PCBs instead of through them.
Samtec’s FireFly™ Micro Flyover System™ was developed for just this purpose. FireFly™ is the first interconnect system that gives designers a choice of using either micro footprint optical or copper interconnects at data rates up to 28 Gbps. This enables an upgrade path from electrical to optical FireFly™ using the same PCB connector system.
The FireFly™ optical solutions provide many benefits. PCB routing is simplified since the optical engine can be placed adjacent to the system IC. Due to its small size, bandwidth density increases and system assembly is simplified. By avoiding “lossy” PCBs, system signal integrity improves enabling lower drive voltages from system ICs saving power.
In previous blogs, Samtec has demonstrated the performance of FireFly™ Micro Flyover System™ at 28 Gbps using pattern generators and similar test equipment. As 2015 came to a close, multiple semiconductors manufacturers have released prototype and production silicon with transceivers running at data rates up to 33 Gbps. As an example, Xilinx and Altera continually battle for the fastest FPGAs.
25 Gbps+ Loop Back Demonstration
With 25 Gbps+ silicon now available, Samtec and their partners are now developing multiple solutions demonstrating the high-speed capabilities of the FireFly™ Micro Flyover System™. In late 2015, Samtec and Xilinx collaborated on a loop-back demonstration using FireFly™ and the Xilinx Virtex UltraScale FPGA running at 25 Gbps+. A simplified block diagram of the set-up is shown below:

Here is a picture of the actual test set-up:

Key test set-up hardware included:
- Xilinx Virtex UltraScale FPGA VCU1287 Characterization Kit
- FireFly™ Test Kits (one transmit and one receive)
- FireFly™ Active Optical Cable Micro Flyover Assemblies (one transmit and one receive)
- Multiple Bull’s Eye® High Speed Cable Assemblies
- 100m OM3 fiber optics cable
The test loop-back demonstration leverages the IBERT for UltraScale GTY Transceivers found with Xilinx’s Vivado Design Suite. Using this tool, Samtec and Xilinx were able to successfully demonstrate four consecutive high-speed serial channels operating at 25.78 Gbps simultaneously error free.
Here is a screen capture and eye-diagram of the results:
Several other test set-ups were run with various data patterns and BER rates to provide further of the FireFly™ operating at data rates up to 28 Gbps.
Stay Updated
If you’d like to discuss this demonstration or learn how it can fit in to your system, please contact the FireFly™ experts. As 2016 progresses, Samtec will release other FireFly™ solutions operating at data rates up to 28 Gbps. Sign-up for the Samtec blog to stay updated on these developments.
For more information on Samtec’s FireFly™ Micro Flyover System™, please download the following resources: