Smiths Connectors is now Smiths Interconnect


Quadrax and twinax contacts are designed for transmission of Ethernet high speed signal in harsh environments where integrity and reliability are essential. Consisting of an outer shield and either two (twinax) or four (quadrax) inner contacts, the high speed copper contacts can be setup in a number of formats including MIL-DTL-38999, ARINC 600, MIL-DTL-83527 and D-subminiature.


  • Data rates exceeding 2 Gbps
  • Matched impedance solutions for 100, 110 and 150 Ω characteristic applications
  • Bandwidth: up to 3 GHz
  • High speed data transmission
  • Minimized jitter and data rate errors
  • Manufacturing protocols: Fibre Channel, Ethernet Firewire, USB, DVI and InfiniBand


While serial data bus has long served as the backbone bus in systems, more demanding data intensive mission requirements including video, audio and data-distribution, have pushed serial data bus of 1 Mbit/Sec beyond the limits of its bandwidth. Today’s serial transmission rate will no longer support these requirements.

However, the commercially available interconnects used for these different topographies will also not survive in the harsh environmental and mechanical environments required for some systems. This shortfall has resulted in the application of high-speed office-based bus structures adapted for higher data rate systems.

  • Fibre Channel
  • Ethernet 100 Base-T
  • 1394b Firewire
  • Gigabit Ethernet, Intellibus, Infiniband

To achieve the data rates that are required for the above listed protocols differential twinax and quadrax contacts were developed. The signal to signal and signal to shield characteristic impedance is maintained throughout the connector pair. A true twinaxial connector interface ensures signal integrity while minimizing jitter and data rate errors.

Twinax Contacts
Consist of an outer shield with two inner contacts spaced to form a 100 Ohm, 110 Ohm or 150 Ohm controlled impedance differential pair.

Quadrax Contacts
Consist of an outer shield with four inner conductors paired orthogonally forming two 100 Ohm, 110 Ohm or 150 Ohm controlled impedance differential pairs. Quadrax contacts offer several advantages for high data transfer rates, low power consumption and excellent EMI compatibility. Four strategically spaced inner contacts form two 100, 110 or 150 ohm matches impedance differential pairs. Outer contact has rugged wall section for durability

Electrical Performance

  • Bandwidth: Up to 3 Gigahertz
  • Data Rates: 100 Mbps – 4 Gbps and beyond

Connector Formats
Smiths Connectors is currently shipping connectors with Twinax and Quadrax contacts in all of the following formats:

Signal Integrity
Making sure that properly shaped pulses reach the receiver.

Eye Pattern
A graph that overlays thousands of pulses as a easy way to check their Signal Integrity.

Undesired coupling between nearby lines.

Difference in Time Delay between Different Signal Paths

Noise induced Timing Errors

Edge Rates
Risetime & Falltime

ElectroMagnetic Interference

Giga Bits per Second

Pseudo Random Bit Stream

Bit Error Rate

Bit Error Rate Test or Tester

Near End Crosstalk

Far End Crosstalk

Inter-Symbol Interference

Low-Voltage Differential Signaling

An interconnection panel into which PC Boards can be plugged