Arista Networks QDD-400G-FR4 Compatible 400G QSFP-DD FR4 Transceiver Module

Built for hosts recognizing QDD-400G-FR4, this HT-manufactured QSFP-DD module delivers 400G transmission at 1271nm,1291nm,1311nm,1331nm. Its rated reach is 2km, with Duplex LC/UPC as the physical interface. The specifications and engineering guidance below support high-density deployments balance optical performance, port access and thermal planning, while keeping HT manufacture separate from the OEM cross-reference.
OEM Part Number: QDD-400G-FR4HT Part Number: QDD-FR4-400G
Product Highlights
- Compatible alternative to Arista Networks QDD-400G-FR4
- 400G connectivity at 400Gbps
- Optical wavelength: 1271nm,1291nm,1311nm,1331nm
- Specified reach: 2km
- Duplex LC/UPC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| Arista Networks Compatible | QDD-400G-FR4 |
|---|---|
| Manufacturer | HT |
| HT Part Number | QDD-FR4-400G |
| Form Factor | QSFP-DD |
| Max. Data Rate | 400Gbps |
| Wavelength | 1271nm,1291nm,1311nm,1331nm |
| Max. Cable Distance | 2km |
| Connector | Duplex LC/UPC |
| Media | SMF |
| Transmitter Type | CWDM EML |
| Receiver Type | PIN |
| TX Power | -3.2~4.4dBm |
| Minimum Receiver Power | -7.2dBm |
| Power Budget | 4dB |
| Receiver Overload | 4.4dBm |
| Max. Power Consumption | 9W |
| Extinction Ratio | 3.5dB |
| DDM/DOM | Supported |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation (Electrical) | 8x50G-PAM4 |
| Modulation (Optical) | 4x100G-PAM4 |
| DSP | TX and RX |
| Inbuilt FEC | No |
| Core Size | G.652/9um |
| Packaging Technology | COB (Chip on Board) Packaging |
| Protocols | QSFP-DD MSA, CMIS.5.0, IEEE 802.3bs |
Applications and Optical Link Design
Use this module for equipment interconnection over the specified single-mode fiber plant, including enterprise backbone, campus, metro or data-center interconnect links according to its rated distance. Confirm that both ends use the same optical standard and wavelength plan, and allow for connector, splice and patch-panel loss within the stated power budget.
Before deployment, check the host port type, supported data rate and firmware requirements. The 400G interface configuration must match the remote equipment; sharing a QSFP-DD housing alone does not make two transceiver types interoperable.
The single-mode link budget should include fiber attenuation, connectors, splices and panels over the intended 2km route. Keep the Duplex LC/UPC interface clean and match the remote optical standard. Consider receiver overload as well as insufficient power on short links.
Quality Assurance and Packaging
Each QDD-400G-FR4 compatible module is inspected, powered up and functionally checked before protective packing. Dust caps and individual trays shield the interface during transport. Customer references, rack groups and project packing lists can be added for volume orders.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -3.2~4.4dBm; the stated optical power budget is 4dB. During commissioning, record the host diagnostic readings after the link has stabilized and compare them with those limits. DOM values are useful operational indicators, but they do not replace calibrated optical measurements when a link is marginal. Investigate unexpected loss through connector inspection, cleaning and a channel measurement before replacing the module. Diagnostic monitoring is listed as Supported. Before every insertion, keep dust caps in place until the patch lead is ready, avoid touching the optical end face and use an appropriate inspection and cleaning procedure. Do not look into an active optical interface.
High-Density Port and Thermal Planning
In a densely populated chassis, connector access and airflow form part of the optical-link design. Confirm that neighboring modules and patch leads leave room for latch operation, and include listed power consumption in the host thermal budget. Assess port density together with fiber management. For this model, the principal parameters are data rate 400Gbps, wavelength 1271nm,1291nm,1311nm,1331nm, rated reach 2km.
Ordering Information
Quote HT part number QDD-FR4-400G together with OEM reference QDD-400G-FR4 and quantity. Add the host model and software release when pre-order verification is required. Neutral labels, customer packaging and project-specific compatibility review are available on request.
Arista Networks Compatibility and Factory Testing
The module is checked for host recognition as QDD-400G-FR4, link establishment and diagnostic reporting. Physical cage fit alone is not treated as evidence of compatibility. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Frequently Asked Questions
Is this an original Arista Networks transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QDD-400G-FR4, not an original Arista Networks-branded module.
Which fiber and connector are required?
Use Duplex LC/UPC with SMF. The specified maximum reach is 2km, subject to fiber quality and total link loss.
Can it be mixed with another wavelength or reach version?
Only when the two ends share the same optical standard, wavelength plan and supported data rate. Check the exact part numbers and link budget rather than relying only on the module form factor.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.
10/100BASE-T SFP