Direct Attach Copper (DAC) Cable

Volex is a leading manufacturer and supplier of Direct Attach Copper (DAC) cable. The Volex DAC cable product family is comprised of cable assemblies with Small Form-factor Pluggable (SFP), Quad Small Form-factor Pluggable (QSFP) and Octal Small Form-factor Pluggable (OSFP) single and double density series modules. Volex offers a full line of active and passive direct attach copper cables from 10Gbps SFP+ to 800Gbps OSFP and QSFP-DD800 designed to meet the requirements of the most demanding data centres with industry leading quality and reliability.

Direct Attach Copper (DAC) Cable Technical Information

DAC cable from Volex is offered with many different form factors, total speeds, lane speeds and lengths in straight and various breakout configurations. See table below:

Volex Direct Attach Copper Cable Products Total Speed (Gbps) Lanes, Lane Speed (Gbps) Lengths (M) Twinax (n-pair) Application
10Gbps SFP+ and 40Gbps QSFP+
SFP+ Passive DAC Cable 10 1, 10 0.5 – 5 2 E, F
QSFP+ Passive DAC Cable 40 4, 10 8 E, I, F
QSFP+ to 4x SFP+ Passive Breakout DAC Cable 40/ 4x 10 4, 10 4x 2 E. F
25Gbps SFP28 and 100Gbps QSFP28
SFP28 Passive DAC Cable 25 1, 25 0.5 – 5 2 E, F
QSFP28 Active DAC Cable 100 4, 25 4 – 9 8 E, I, F
QSFP28 Passive DAC Cable 100 4, 25 0.5 – 5 8 E, I , F
QSFP28 to 2x QSFP28 Active Breakout DAC Cable 100/ 2x 50 4, 25 4 – 9 2x 4 E
QSFP28 to 2x QSFP28 Passive Breakout DAC Cable 100/ 2x 50 4, 25 0.5 – 5 2x 4 E
QSFP28 to 4x SFP28 Active Breakout DAC Cable 100/ 4x 25 4, 25 4 – 9 2x 4 E
QSFP28 to 4x SFP28 Passive Breakout DAC Cable 100/ 4x 25 4, 25 0.5 – 5 4x 2 E, F
50Gbps SFP56, 100Gbps SFP-DD and 200Gbps QSFP56
SFP56 Passive DAC Cable 50 1, 50 0.5 – 3 2 E. F
SFP-DD Passive DAC Cable 100 2, 50 0.5 – 3 4 E, F
QSFP56 Active DAC Cable 200 4, 50 4 – 9 8 E, I, F
QSFP56 Passive DAC Cable 200 4, 50 0.5 – 3 8 E, I, F
QSFP56 to 2x QSFP56 Active Breakout DAC Cable 200/ 2x 100 4, 50 4 – 9 2x 4 E, I
QSFP56 to 2x QSFP56 Passive Breakout DAC Cable 200/ 2x 100 4, 50 0.5 – 3 2x 4 E, I
QSFP56 to 4x SFP56 Active Breakout DAC Cable 200/ 4x 50 4, 50 4 – 9 4x 2 E, F
QSFP56 to 4x SFP56 Passive Breakout DAC Cable 200/ 4x 50 4, 50 0.5 – 3 4x 2 E, F
400Gbps QSFP-DD and OSFP
QSFP-DD Active DAC Cable 400 8, 50 4 – 9 16 E
QSFP-DD Passive DAC Cable 400 8. 50 0.5 – 3 16 E
QSFP-DD to 2x QSFP56 Passive Breakout DAC Cable 400/ 2x 200 8, 50 0.5 – 3 2x 8 E
QSFP-DD to 4x QSFP56 Passive Breakout DAC Cable 400/ 4x 100 8, 50 0.5 – 3 4x 4 E
OSFP 400G Passive DAC Cable 400 8, 50 0.5 – 3 16 E
400Gbps QSFP112, 800G OSFP and QSFP-DD800
QSFP112 Active DAC Cable 400 4, 100 1 – 5 8 E
QSFP112 Passive DAC Cable 400 4, 100 0.5 – 2 8 E
800G OSFP Passive DAC Cable 800 8, 100 0.5 – 2 16 E
QSFP-DD800 Passive DAC Cable 800 8, 100 0.5 – 2 16 E
E = Ethernet, I = InfiniBand, F = Fibre Channel

For each product line, different lengths (meters) and wire gauges (AWG) and other customisation options including pull-tab colour, low-smoke zero-halogen cable jacket and colour, and EEPROM custom programming and pages are available.

Applications / Market for Direct Attach Copper (DAC) Cable

DAC cable is used for data connection applications in high-speed data centres.

Examples:

  • Servers
  • Switches
  • Routers
  • High-performance Computing
  • Storage

What is Direct Attach Copper (DAC) Cable?

Direct attach cables are factory terminated copper cable assemblies with SFP, QSFP and OSFP single and double density series pluggable modules.

Low cost and low power consumption with no heat produced and very high reliability make passive DAC the preferred choice for short distance (1-5M) data centre in-rack equipment interconnect application. Active DAC can preserve signal integrity with embedded retimer or redriver extending the reach up to 9M for inter-rack interconnect application. Active DAC also can be an option for cabling high density rack with thinner and more flexible cables.

Benefits of Direct Attach Copper (DAC) Cable

DAC Cables from Volex are optimised for Ethernet, Infiniband and Fibre Channel data connection applications in data centres, with benefits that include:

  • Near-zero power consumption, low heat dissipation, very low cost
  • Complete cable assembly uniquely terminated at the factory to provide the most reliable operation
  • 100% tested for signal integrity with serial number traceability
  • Product customisation available to meet customer specifications
  • Production capacity to meet mega sized global data centre demand
  • Innovative design development to support next-generation interconnect technology and deployment
Features Benefits
Wide AWG range Provides cost, reach, signal integrity margin and cable flexibility optimisation
Passive copper length up to 6 metres Meets industry standard signal integrity requirements up to lengths of 6 metres (varies depending on cable speed)
Unique foam dielectric cable jacket construction Increased flexibility cables while maintaining signal integrity quality
Custom EEPROM programming Programmable to customer requirements
Optimised PCB design Provides superior margin for 24G NRZ, 50G PAM4 and 100G PAM4 signal integrity parameters against standard specification
Advanced wire stripping and cable termination process Eliminate damage to the conductor and shield, prevent dielectric shrink back, protect solder joints, reinforced strain relief, all while maintaining signal integrity, product quality, and operational reliability
LSZH cable jacket and PCB options Environmentally friendly
Custom solutions supported Custom solutions forcible configuration, connector pin repurposing and beyond

Why Choose Volex for Direct Attach Copper (DAC) Cable?

Volex’s engineering teams can customise a solution to a customer’s specific requirements and provide quick turn custom design samples supported by skilled local sales and field applications engineering (FAE) teams. A global factory footprint, which includes tariff-free manufacturing sites, efficient global supply chain and logistics support, enables reduced product lead time and efficient cost management.

By partnering with Volex on data centre high-speed interconnect solutions, customers benefit from strong technical expertise and manufacturing prowess to help future-proof data centres and fulfil infrastructure development and growth goals.

Contact Volex for Direct Attach Copper (DAC) Cable

Contact Volex for further assistance with DAC cable.