QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT 400G QSFP-DD 8 x 50G PAM4 to 2 x 200G QSFP56 4 x 50G PAM4 Passive Copper Breakout Cable, 2.5m (8ft)

Product Highlights

• HT-manufactured DAC assembly in 2.5m (8ft)
• 400G connectivity at 400Gbps
• Interface configuration: QSFP-DD to 2x QSFP56
• Fixed length and part number: 2.5m (8ft), QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT
• Cable construction: Passive Twinax
• Conductor specification: 28AWG
• Maximum power consumption: 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End)
• Minimum bend radius: 39.5mm

Specifications

Power and Thermal Planning

The rated power consumption is 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End). Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.

Network and Protocol Considerations

The intended application is 400G Ethernet. Listed interface and protocol references include IEEE802.3Bj, By, IEEE802.3CD, SFF-8679, SFF-8636. Confirm that the host firmware and port configuration support the same operating mode.

Breakout Port Mapping

The QSFP-DD to 2x QSFP56 configuration divides the high-speed interface into multiple lower-speed connections. Verify the upstream lane assignment, downstream port speeds and breakout setting on the host before connecting the assembly. Each branch must attach to the correct remote interface.

Passive Copper Operation

A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.

Length Selection and Installation Planning

The 2.5m (8ft) version is useful when a two-metre run would leave insufficient working slack. Before installation, check the complete horizontal and vertical path so that QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT reaches both ports without tension at either connector.

Position Within the Length Range

QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT occupies the middle of this family between QSFP-DD to 2x QSFP56-400G-DAC-2M7FT at 2m (7ft) and QSFP-DD to 2x QSFP56-400G-DAC-3M10FT at 3m (10ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

Mixed-Vendor Network Operation

A mixed-vendor link should be documented at both ends, not treated as one generic connection. Confirm which OEM identity each host expects and whether the two ends use the same compatibility requirement. The related brand links below help locate equivalent-length assemblies, while the physical form factor and lane arrangement must still agree across the complete path. For this assembly, the listed conductor specification is 28AWG; the minimum bend radius is 39.5mm; the stated power consumption is 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End); the jacket material is PVC.

Cable Construction and Routing

This assembly uses 28AWG conductors, PVC jacket, minimum bend radius 39.5mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.

Generic Compatibility and Factory Testing

Testing addresses the brand-specific identification as well as the operating link and available diagnostics. The same physical cable family can require a different host identity for another equipment vendor, so the intended platform should be supplied when a deployment combines multiple brands or unusual hardware revisions. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.

Ordering Information

For mixed-vendor projects, identify the equipment at both ends along with the OEM reference, length and quantity. Order each compatibility version under its own part number. If spare assemblies are required, list them separately so labels and test records remain unambiguous. This page’s fixed configuration is 2.5m (8ft); another length must be quoted under its corresponding part number.

Quality Assurance and Packaging

Both ends are inspected and the complete assembly is powered up for a functional check before packing. Connectors are protected individually and the cable is secured without tight bends. Optional labels can distinguish host brand, OEM reference and length for easier spares management. Volume orders can include customer references on the labels and carton list.

Frequently Asked Questions

Shipping and Lead Time

Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. International express, air cargo and sea freight can be selected according to destination and carton volume; customer courier accounts and nominated forwarders are also accepted.