NVIDIA/Mellanox SFP1G-LX-31-I Compatible 1.25G SFP Transceiver Module

This NVIDIA/Mellanox SFP1G-LX-31-I compatible transceiver provides 1.25G connectivity in a hot-swappable SFP package. Its optical design operates at 1310nm for up to 10km on SMF, using Duplex LC. Complete parameters and related OEM references help procurement teams match an equipment parts list to a clearly defined optical product.
OEM Part Number: SFP1G-LX-31-IHT Part Number: SFP1G-LX-31
Product Highlights
- Compatible alternative to NVIDIA/Mellanox SFP1G-LX-31-I
- 1.25G connectivity at 1.25Gbps
- Optical wavelength: 1310nm
- Specified reach: 10km on SMF
- Duplex LC / SMF interface
- Operating temperature: -40 to 85°C (-40 to 185°F)
- Factory compatibility verification and optical performance testing before shipment
Specifications
| HT Part Number | SFP1G-LX-31 |
|---|---|
| Manufacturer | HT |
| Form Factor | SFP |
| Max. Data Rate | 1.25Gbps |
| Wavelength | 1310nm |
| Max. Cable Distance | 10km@SMF |
| Connector | Duplex LC |
| Optical Components | FP 1310nm |
| Media | SMF |
| DOM Support | Yes |
| TX Power | -9.0~-3dBm |
| Receiver Sensitivity | < -21dBm |
| Industrial Temperature Range | -40 to 85°C (-40 to 185°F) |
| Protocols | IEEE 802.3z, SFF-8472, FC-PI, SFP MSA (INF-8074i) Compliant |
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.
The industrial temperature rating makes this version appropriate for controlled outdoor cabinets, transport nodes and other installations exposed to wider ambient temperature variation. Adequate airflow, protected cable routing and host-platform temperature limits still apply.
Before commissioning, measure the complete single-mode channel against the stated budget for 10km on SMF. Inspect every Duplex LC connection and record diagnostic power where supported. Both ends must agree on rate, wavelength and optical standard.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -9.0~-3dBm; receiver sensitivity is < -21dBm. A sound acceptance record includes link state, diagnostic temperature, supply voltage and transmit or receive levels where the host exposes them. Compare the readings with the stated ranges rather than treating any received light as proof of adequate margin. Persistent alarms or borderline values should trigger an end-face and complete-channel inspection. 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.
Procurement and Asset Identification
A useful purchase order identifies the host platform, expected OEM code and optical standard separately. This prevents a module with the same housing but another wavelength, reach or identification profile from being substituted. For mixed deployments, keep one order line per OEM reference and reconcile each received unit with its intended port. For this model, the principal parameters are data rate 1.25Gbps, wavelength 1310nm, rated reach 10km on SMF.
NVIDIA/Mellanox Compatibility and Factory Testing
Compatibility testing for SFP1G-LX-31-I combines identification with a live link and available transmit, receive and alarm information. Connector condition is inspected separately. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Ordering Information
When ordering, specify SFP1G-LX-31-I, SFP1G-LX-31, quantity and intended host platform. Project labels can repeat these details for receiving and asset records. Neutral labels, customer packaging and project-specific compatibility review are available on request.
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.
Frequently Asked Questions
Is this an original NVIDIA/Mellanox transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies SFP1G-LX-31-I, not an original NVIDIA/Mellanox-branded module.
Which fiber and connector are required?
Use Duplex LC with SMF. The specified maximum reach is 10km on SMF, 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.