Broadcom QDD-ER4L-400G Compatible 400G QSFP-DD ER4L Transceiver Module
The QDD-ER4L-400G compatible module serves equipment requiring a 400G QSFP-DD interface with 1310nm optics and a 30km rating. Connection is through Duplex LC/UPC. Product data, application guidance and factory verification are presented together to support project teams keep OEM references, delivery records and port schedules aligned.
OEM Part Number: QDD-ER4L-400GHT Part Number: QDD-ER4L-400G
Product Highlights
- Compatible alternative to Broadcom QDD-ER4L-400G
- 400G connectivity at 400Gbps
- Optical wavelength: 1310nm
- Specified reach: 30km
- Duplex LC/UPC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| HT Part Number | QDD-ER4L-400G |
|---|---|
| Manufacturer | HT |
| Form Factor | QSFP-DD |
| Max. Data Rate | 400Gbps |
| Wavelength | 1310nm |
| Max. Cable Distance | 30km |
| Connector | Duplex LC/UPC |
| Media | SMF |
| Transmitter Type | EML |
| Receiver Type | APD |
| TX Power | 0.4~6.5dBm |
| Minimum Receiver Power | -10.1dBm |
| Power Budget | 10.5dB |
| Receiver Overload | -3.4dB |
| Max Power Consumption | 12W |
| Extinction Ratio | 6dB |
| DDM/DOM | Supported |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation (Electrical) | 8x53.125G-PAM4 |
| Modulation (Optical) | 4x106.25G-PAM4 |
| DSP | TX and RX |
| Inbuilt FEC | No |
| Bit Error Ratio (BER) | 2.4E-4 |
| MTBF | 2050000 Hours (@40°C, 60% CL)818000 Hours (@40°C, 90% CL)1300000 Hours (@55°C, 60% CL)519000 Hours (@55°C, 90% CL) |
| Packaging Technology | BOX |
| Application | Data Center, Enterprise Networking, 400G Ethernet |
| Protocols | QSFP-DD MSA, CMIS Rev4.0, IEEE 802.3, IEEE 802.3bs, OIF 56G PAM4 |
Project Documentation and Traceability
Large deployments are easier to audit when the order code, optical standard and endpoint record agree. Keep the OEM reference in the compatibility document and the HT part number on the packing list. Labels and carton groups can be arranged by rack or port plan so installers need not identify modules by appearance. For this model, the principal parameters are data rate 400Gbps, wavelength 1310nm, rated reach 30km.
Broadcom Compatibility and Factory Testing
Factory verification starts with the expected QDD-ER4L-400G identity and finishes with an operating host link. EEPROM data, diagnostic visibility and the stated optical parameters are assessed together. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Applications and Optical Link Design
This coherent interface is suited to data-center interconnect, metro transport and managed DWDM links where the host platform supports the stated modulation and FEC modes. Design the optical line around the actual launch power, receiver range, OSNR requirement and span loss; the stated reach is not a substitute for a link-budget calculation. Use matching coherent modules and the appropriate DWDM channel plan at both ends.
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.
For this coherent interface, document the wavelength plan and modulation or FEC settings before commissioning. Measure span loss and verify adequate OSNR. Interoperability depends on compatible coherent modes as well as form factor, so another coherent part number must not be substituted without engineering review.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is 0.4~6.5dBm; the stated optical power budget is 10.5dB. 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.
Frequently Asked Questions
Is this an original Broadcom transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QDD-ER4L-400G, not an original Broadcom-branded module.
Which fiber and connector are required?
Use Duplex LC/UPC with SMF. The specified maximum reach is 30km, 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.
Ordering Information
Use QDD-ER4L-400G as the compatibility cross-reference and QDD-ER4L-400G as the HT ordering identity. Keep other reaches or wavelength directions on separate order lines. Neutral labels, customer packaging and project-specific compatibility review are available on request.
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.
Quality Assurance and Packaging
Before packing, the module receives interface inspection, identification and link checks. Protective packaging avoids pressure on the connector and latch. Customer references, rack groups and project packing lists can be added for volume orders.
