QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT 400G QSFP-DD 8 x 50G PAM4 to 2 x 200G QSFP56 4 x 50G PAM4 Passive Copper Breakout Cable, 0.5m (2ft)

This page covers one precise cable-schedule item: Generic QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT in 0.5m (2ft), supporting 400G operation through QSFP-DD to 2x QSFP56. The complete DAC assembly is identified separately from other lengths and includes verified specifications, change-control-friendly ordering details and live-link factory checks.
OEM Part Number: QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FTHT Part Number: QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT
Product Highlights
- HT-manufactured DAC assembly in 0.5m (2ft)
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to 2x QSFP56
- Fixed length and part number: 0.5m (2ft), QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT
- Cable construction: Passive Twinax
- Conductor specification: 30AWG
- Maximum power consumption: 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End)
- Minimum bend radius: 33.5mm
Specifications
| HT Part Number | QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT |
|---|---|
| Manufacturer | HT |
| Connector Type | QSFP-DD to 2x QSFP56 |
| Max Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Twinax |
| Cable Length | 0.5m (2ft) |
| Wire AWG | 30AWG |
| Minimum Bend Radius | 33.5mm |
| Max. Power Consumption | 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End) |
| Jacket Material | PVC |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Protocols | IEEE802.3Bj, By, IEEE802.3CD, SFF-8679, SFF-8636 |
| Application | 400G Ethernet |
| Modulation Technology | PAM4 |
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.
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 0.5m (2ft) length is suited to closely aligned ports where excessive slack would obstruct airflow or complicate dressing. Measure the actual port-to-port path before choosing QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.
Position Within the Length Range
QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT is the shortest of 6 verified length options in this family. It is the preferred choice when the port positions are close and cable slack must be kept to a minimum. The next option is QSFP-DD to 2x QSFP56-400G-DAC-1M3FT at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.
Structured Pathways and Serviceability
Treat the direct-attach assembly as part of the permanent pathway plan even when the link is expected to be temporary. Follow the intended horizontal and vertical managers, maintain the specified bend radius and leave service access around both ports. A small, supported service allowance is preferable to excess slack concealed inside a rack or placed under cable-tie pressure. For this assembly, the listed conductor specification is 30AWG; the minimum bend radius is 33.5mm; 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 30AWG conductors, PVC jacket, minimum bend radius 33.5mm. 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.
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.
Ordering Information
Include the part number, fixed length, quantity and required pathway or rack grouping in the order information. The host model and firmware release are useful for change-controlled deployments. Different lengths should remain separate order lines so delivered labels and packing records agree with the pathway plan. Quantity and any labeling instructions should be attached specifically to QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT.
Generic Compatibility and Factory Testing
Verification covers the physical connectors, expected host identity and an operating link with available diagnostic indications. We distinguish this complete check from a simple continuity test. Platform model and software release can be reviewed in advance where the installation has strict documentation or change-control requirements. Where supported by the host, link stability and diagnostic indications are reviewed together with the established link.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. Delivery can be arranged by courier, air freight or sea freight, and goods may instead be handed to an appointed forwarder or shipped on the customer’s courier account.
Quality Assurance and Packaging
After connector inspection and link verification, the assembly is coiled without tight bends and packed with end protection. Labels can cross-reference the customer cable schedule, OEM part number and length. This supports both receiving checks and later moves, adds or changes. Neutral packaging and customer-specific packing documentation are available on request.
Frequently Asked Questions
Is this an original equipment manufacturer cable?
No. It is manufactured by HT under our own manufacturer identity.
Are separate transceivers or patch leads required?
No. This is one complete direct-attach assembly. The ends are not detachable modules and should not be separated from the cable.
Can excess cable be folded into a compact bundle?
No. Use a supported, bend-safe service loop and observe the listed minimum bend radius. Do not crease the cable or tighten ties around the connector boots.
Will any matching connector operate at the same speed?
Not necessarily. Both hosts must support the stated rate, identification, lane mapping and any required breakout configuration; mechanical compatibility alone is insufficient.
QSFP-DD to 2x QSFP56-400G-DAC-0.5M2FT