Specifications, compatibility and ordering information
The 400G QSFP-DD FR4 optical transceiver is designed for 400G links up to 2km over single-mode fiber, using four CWDM optical wavelengths and a duplex LC interface. Its 1271, 1291, 1311 and 1331nm channels are multiplexed onto a duplex fiber pair, making FR4 a practical option for projects where the installed cabling is based on LC single-mode links rather than the parallel MPO infrastructure required by DR4 or SR8. Host FEC is required for the specified 2km transmission distance.
For a procurement team, the important point is to approve the complete link configuration rather than purchasing on “400G QSFP-DD” alone. When comparing products in the 400G optical transceiver range, the target switch or NIC, duplex SMF path, required reach, host FEC and any platform-specific compatibility or coding should be checked together. A physically compatible QSFP-DD port does not make an FR4 module interchangeable with a DR4 or SR8 module because the optical interface and cabling architecture are different.
Before a volume PO is released, the agreed product version should be tied to the commercial order, including quantity, compatibility requirements, labeling, packaging and any documentation needed for the project. Delivery and payment terms should also be confirmed with the order rather than assumed from a standard product configuration. At receiving, the FR4 designation, QSFP-DD form factor, duplex LC interface, 2km rating, labels, quantity and any agreed coding should be checked against the approved purchase specification before the batch is released for installation.
400G QSFP-DD FR4 Specifications
The specifications below focus on the optical path, host requirements and operating characteristics that most directly affect whether this module matches an approved 400G FR4 deployment.
| Specification | Value |
|---|---|
| Supported Data Rate | Up to 425Gbps |
| Form Factor | QSFP-DD |
| Optical Type | 400G FR4 |
| Optical Architecture | 4-channel CWDM MUX/DEMUX |
| Center Wavelengths | 1271 / 1291 / 1311 / 1331nm |
| Laser Type | EML |
| Electrical Interface | 8 × 53.125Gbps PAM4 |
| Fiber Type | Single-Mode Fiber |
| Transmission Distance | Up to 2km with Host FEC |
| Optical Interface | Duplex LC |
| Operating Case Temperature | 0°C to 70°C |
| Power Supply | 3.3V |
| Power Dissipation | <10W |
| Digital Diagnostic Monitoring | Supported via I2C |
| Management Interface | CMIS 4.0 |
For bulk sourcing, the most important acceptance points are the FR4 optical type, duplex LC interface, 2km SMF requirement and host-side compatibility. These items should remain consistent from technical approval through quotation and shipment. Incoming inspection can then use the approved specification, labels and agreed coding as the basis for confirming that the received modules are the same configuration selected for the project.
