10/100BASE-T SFPHPE Aruba S4B38A Compatible 400G QSFP-DD Transceiver Module
Built for hosts recognizing S4B38A, this HT-manufactured QSFP-DD module delivers 400G transmission at 1528.77~1566.52nm. Its rated reach is Amplified: ≤120km Unamplified：≤40km, 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: S4B38AHT Part Number: QDD-ZR-400G
Product Highlights
- Compatible alternative to HPE Aruba S4B38A
- 400G connectivity at 400Gbps
- Optical wavelength: 1528.77~1566.52nm
- Specified reach: Amplified: ≤120km Unamplified：≤40km
- Duplex LC/UPC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0℃ to 70°C(32 to 158°F)
Specifications
| Aruba Compatible | S4B38A |
|---|---|
| Manufacturer | HT |
| HT Part Number | QDD-ZR-400G |
| Form Factor | QSFP-DD |
| Max. Data Rate | 400Gbps |
| Wavelength | 1528.77~1566.52nm |
| Max. Cable Distance | Amplified: ≤120km Unamplified：≤40km |
| Connector | Duplex LC/UPC |
| Media | SMF |
| TX Power | -13~-9dBm |
| RX Power | Amplified: Full Rx OSNR tolerance: -12~0dBm Extended range: -15~1dBm Unamplified: -20~0dBm |
| Max. Power Consumption | 18.5W |
| Minimum Receiver Power | Amplified: -12dBm Unamplified: -20dBm |
| DDM/DOM | Supported |
| Commercial Temperature Range | 0℃ to 70°C(32 to 158°F) |
| Inbuilt FEC | CFEC |
| Modulation Format | DP-16QAM |
| CD Robustness | 2400(ps/nm) |
| OSNR Tolerance | 26dB/0.1nm |
| Protocols | OIF 400ZR, OIF-CMIS-05.2, OIF-C-CMIS-01.2, QSFP-DD-Hardware-Rev6.3, IEEE Std 802.3-2018 |
| Application | Edge DCI |
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.
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.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -13~-9dBm. 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 1528.77~1566.52nm, rated reach Amplified: ≤120km Unamplified：≤40km.
Ordering Information
Use S4B38A as the compatibility cross-reference and QDD-ZR-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.
HPE Aruba Compatibility and Factory Testing
The module is checked for host recognition as S4B38A, 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 HPE Aruba transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies S4B38A, not an original HPE Aruba-branded module.
Which fiber and connector are required?
Use Duplex LC/UPC with SMF. The specified maximum reach is Amplified: ≤120km Unamplified：≤40km, 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.
