400G QSFP-DD to 2×200G QSFP56 Active Optical Cable (AOC) – PAM4

• Supports 400Gbps to 2×200Gbps breakout connectivity
• QSFP-DD to 2×QSFP56 configuration
• Supports 8×50Gbps PAM4 modulation
• Multimode fiber (MMF) transmission
• Available in cable lengths from 0.5m to 50m
• Compliant with CMIS 4.0
• Hot-pluggable QSFP-DD and QSFP56 interfaces
• Single 3.3V power supply
• Maximum power dissipation of 8W at the QSFP-DD end
• Maximum power dissipation of 4.5W at each QSFP56 end
• Commercial operating case temperature of 0°C to +70°C
• Designed for high-density 400G-to-2×200G breakout architectures
• RoHS compliant

• 400GbE to 2×200GbE breakout connections
• 400G data center switch-to-2×200G switch connectivity
• AI and GPU cluster networking
• High-performance computing (HPC)
• High-density Ethernet switching
• Spine-and-leaf data center architectures
• Server and network adapter interconnections
• Top-of-rack (ToR) network deployments
• Short- to medium-distance intra-data-center links

OEM and ODM customization is available for the 400G QSFP-DD to 2×200G QSFP56 AOC Series. Custom options can include cable length, labeling, EEPROM configuration, cable identification, packaging, and other assembly requirements.

Cable lengths can be specified according to the physical layout of the target deployment within the supported 0.5m to 50m range. Customized programming and identification information can also be provided to meet specific equipment-recognition and network management requirements.

How does the 400G-to-2×200G breakout architecture work?

The QSFP-DD end provides a single 400G interface, while the two QSFP56 ends provide two independent 200G interfaces. The cable therefore allows a compatible 400G switch port to connect to two separate 200G ports without requiring separate optical modules and patch cables.

Are the two QSFP56 ends independent 200G links?

Yes. Each QSFP56 end is designed to operate as an independent 200G connection. The host equipment must support the appropriate 400G breakout configuration and recognize the corresponding 200G interfaces.

Why use an AOC for a 400G-to-2×200G connection?

An AOC integrates the optical conversion components into the cable assembly, providing a ready-to-deploy optical link. Compared with a copper breakout cable, the optical design is better suited to longer short-reach connections and can provide greater flexibility for cable routing in high-density environments.

What is the significance of 8×50Gbps PAM4?

The 400G side uses eight electrical lanes, each operating at 50Gbps with PAM4 signaling. PAM4 carries two bits per symbol, enabling high aggregate bandwidth while maintaining a practical lane architecture for the QSFP-DD interface.

Why is the power dissipation specified separately for each end?

The two connector ends contain different active optical and electrical components. The QSFP-DD end supports the 400G interface and has a maximum power dissipation of 8W, while each QSFP56 end supports a 200G interface with a maximum power dissipation of 4.5W. These values are important when planning thermal management and power budgets for high-density equipment.

What cable length should be selected?

The cable length should be based on the physical distance between the 400G host and the two 200G endpoints. For connections within the same rack, a shorter cable helps simplify cable management, while longer options up to 50m provide greater flexibility for equipment located farther apart.