FireFly Micro Flyover System™ is the first interconnect system that gives a designer the flexibility of using micro footprint high-performance optical and low-cost copper interconnects interchangeably with the same connector system.

Samtec FireFly copper and optical cable systems provide the flexibility to achieve higher data rates to 28 Gbps and/or greater distances, simplifying board design and enhancing performance.

The system’s miniature footprint allows for greater density and closer proximity to the IC, enabling chip-to-chip, board-to-board, on-board and system-to-system connectivity.


FireFly Copper

  • Performance to 28 Gbps
  • x4 bidirectional or x12 unidirectional
  • 100 Ω, 34 or 36 AWG Eye Speed® twinax cable
  • Variety of end 2 termination options
  • Low-profile housing for space savings
  • Low-cost solution for seamless integration of new and existing designs
  • Standard copper (ECUE), optimized copper (ECUE-2) and PCIe®-Over-FireFly copper (PCUE) assemblies available

FireFly Optical

  • Performance to 28 Gbps
  • x4 and x12 designs
  • OM3 multi-mode fiber
  • Variety of End 2 options and heat sinks for various cooling processes
  • Extended Temperature FireFly with a -40 ºC to +85 ºC range for military and industrial applications (ETUO)
  • PCIe®-Over-Fiber optical cable system with Gen 3 data transfer rates to 100 m (PCUO)
  • PCIe®-Over-Fiber adaptor card supports transparent and non-transparent bridging (PCOA)


The industry-leading miniature footprint of FireFly™ allows for greater density and closer proximity to the IC, which simplifies board layout and enhances signal integrity. Performance from 14 Gbps to 28 Gbps can be achieved in the same footprint covering an area of only 0.63 square inches for an aggregate 265 Gbps/in².


The two-piece board level interconnect system consists of a micro high-speed edge card connector, and a positive latch connector for power and control signal communications. Isolating the signal and power in this manner helps ease trace routing, compared to array systems.

UEC5 – High-Speed Edge Card Connector
  • Gen 1 – up to 20 Gbps
  • Gen 2 – 20+ Gbps
UCC8 – Positive Latch Connector


The rugged two-piece edge card socket system, with weld tabs, latch locking mechanism, and loading guides, provides simplified mating and unmating of the cable assembly, compared to compression systems, which utilize mechanical screw downs and hardware.

Unlike existing optical engine-based solutions, thermal operating conditions are acknowledged and designed for by including an integral heat sink. This integral heat sink further simplifies the assembly process. Standard heat sinks are available in several designs, including finned, flat, fiber-groove for multi-row configurations, and custom designs, for conduction or convection cooling.


By taking the data connections "off-board" with Samtec Flyover™ cables, the signal integrity design is made significantly easier, and the electrical performance improved.

Routing data above lossy board materials and other signal degrading components negates the need for the layout complexities that are required to design for high speed signaling.


Rated up to 28 Gbps, this kit allows the designer real-time evaluation of an actively running copper or optical FireFly™ system in their lab, with their inputs.

The evaluation board connects the FireFly™ connector system (UEC5/UCC8) to a 24-position Bulls Eye® system and brings the low-speed signals and power rails to various standard connectors. The Bulls Eye® system allows for connecting all 12 FireFly™ channels to various laboratory test equipment. A second Bulls Eye® connector landing pad enables the de-embedding of the Bulls Eye® interconnect and PCB effects on the high-speed signals.



Samtec's 14 Gbps FireFlyTM FMC Module provides up to 140 Gbps full-duplex bandwidth over 10 channels from an FPGA to an industry-standard multi-mode fiber optic cable. The optical engines in FireFlyTM provide adjustable power levels to support cable lengths up to 100 m.

As a VITA 57.1 FMC, the module can be used for optical data communication on any FPGA development board supporting high-speed multi-gigabit transceivers. It can run system data or BERT testing on all channels in parallel. This makes evaluation and development with an FPGA much easier and is an ideal substitute for 28G test equipment.

Part Number: REF-193429-01