NVIDIA/Mellanox SFP-25GMCSR-85 Compatible 25G SFP28 CSR Transceiver Module

Built for hosts recognizing SFP-25GMCSR-85, this HT-manufactured SFP28 module delivers 25G transmission at 850nm. Its rated reach is 400m on OM4 / 300m on OM3, with Duplex LC 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: SFP-25GMCSR-85HT Part Number: SFP-25GMCSR-85
Product Highlights
- Compatible alternative to NVIDIA/Mellanox SFP-25GMCSR-85
- 25G connectivity at 25Gbps
- Optical wavelength: 850nm
- Specified reach: 400m on OM4 / 300m on OM3
- Duplex LC / MMF interface
- Operating temperature: 0 to 70°C (32 to 158°F)
- Factory compatibility verification and optical performance testing before shipment
Specifications
| HT Part Number | SFP-25GMCSR-85 |
|---|---|
| Manufacturer | HT |
| Form Factor | SFP28 |
| Max Data Rate | 25Gbps |
| Wavelength | 850nm |
| Max Cable Distance | 400m@OM4/300m@OM3 |
| Connector | Duplex LC |
| Media | MMF |
| Transmitter Type | VCSEL |
| Receiver Type | Pin |
| TX Power | -6.4~2.4dBm |
| Receiver Sensitivity | <-6dBm |
| Power Budget | -0.4dB |
| Receiver Overload | 2.4dBm |
| Power Consumption | ≤1W |
| Extinction Ratio | >2dB |
| CDR (Clock and Data Recovery) | TX and RX Built-in CDR |
| FEC Function | Support RS-FEC |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Protocols | SFF-8472, SFF-8024, SFF-8431, SFF-8432, IEEE802.3by |
| Core Size | 50/125 µm |
| Packaging Technology | COB Packaging |
| DOM | Supported |
Applications and Optical Link Design
Typical deployments include switch-to-switch, switch-to-server and aggregation links inside a data hall or between adjacent equipment rooms. The Duplex LC interface connects to the specified multimode cabling, and the stated reach depends on fiber grade and link loss. Keep this interface on the matching multimode optical standard rather than connecting it directly to a single-mode wavelength or reach variant.
Before deployment, check the host port type, supported data rate and firmware requirements. The 25G interface configuration must match the remote equipment; sharing a SFP28 housing alone does not make two transceiver types interoperable.
For this multimode module, confirm fiber grade, modal bandwidth and total loss before commissioning. The 400m on OM4 / 300m on OM3 figure applies only under suitable cabling conditions. Inspect every Duplex LC mating point and match the remote optical standard.
Quality Assurance and Packaging
Quality control covers the optical or electrical interface, host identification and operating link. The verified unit is then individually protected and cartoned. 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 -6.4~2.4dBm; receiver sensitivity is <-6dBm; the stated optical power budget is -0.4dB. 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. 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 25Gbps, wavelength 850nm, rated reach 400m on OM4 / 300m on OM3.
Ordering Information
Use SFP-25GMCSR-85 as the compatibility cross-reference and SFP-25GMCSR-85 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.
NVIDIA/Mellanox Compatibility and Factory Testing
The module is checked for host recognition as SFP-25GMCSR-85, 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 NVIDIA/Mellanox transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies SFP-25GMCSR-85, not an original NVIDIA/Mellanox-branded module.
Which fiber and connector are required?
Use Duplex LC with MMF. The specified maximum reach is 400m on OM4 / 300m on OM3, 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.
SFP-25GMCSR-85