1.25G CSFP 1310/1550NM,1310/1490NM 20KM
Carritech Optics 1.25 Gbps Compact SFP BiDi Transceiver (20 km, 1310/1490 nm) is a dual-channel CSFP module designed for cost-efficient Gigabit Ethernet BX20 and FTTH deployments, featuring FP/DFB laser transmitters, PIN receivers, and full digital diagnostic monitoring.
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The hardware listed below is a selection of key popular equipment, not a complete compatibility list. This transceiver may also be compatible with many other hardware models. Contact us and we can check the exact hardware you need.
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The 1.25Gbps 1310/1490nm Compact SFP (CSFP) Transceiver is a high-performance optical module designed for bi-directional data communication over single-mode fiber (SMF) up to 20 kilometers. Encased in a compact SFP form factor with an LC/UPC optical interface, it supports data rates of up to 1250Mbps and complies with the 1000Base-BX20 IEEE802.3ah standard. The module integrates a 1310nm FP laser for upstream transmission, a 1490nm DFB laser for downstream transmission, and a PIN photodetector for reliable performance. Its compliance with CSFP MSA and SFF-8472 standards ensures broad compatibility across networking equipment.
Operating on a single +3.3V power supply, the transceiver is energy-efficient with a power consumption of less than 1.5W. It is designed for commercial applications with a case operating temperature range of 0°C to 70°C. The module’s metal enclosure minimizes electromagnetic interference (EMI), ensuring stable and reliable operation in high-performance networks. RoHS compliance further underscores its environmentally responsible design.
The transceiver’s optical performance is optimized for reliability. The transmitter provides an average output power between -9dBm and -3dBm, with an extinction ratio of 8.2dB. The receiver sensitivity is rated at -19dBm, and the module includes advanced diagnostic features such as Loss of Signal (LOS) detection. The LOS output indicates link status or insufficient optical power, enhancing monitoring capabilities for operational stability.
Electrically, the module features a differential impedance of 100Ω and supports input and output swing differentials to facilitate integration with host systems. Digital diagnostics are accessible via a 2-wire serial interface, providing real-time insights into parameters like temperature, voltage, bias current, and optical power. Alarm and warning thresholds alert users to deviations from optimal operating conditions, ensuring reliability and performance.
In summary, the 1.25Gbps 1310/1490nm Compact SFP Transceiver is a robust and efficient solution for short to medium-range bi-directional optical communication. Its advanced optical and electrical capabilities, combined with compliance to industry standards, make it a valuable component for modern networking and telecommunications infrastructure.
This CSFP transceiver delivers 1.25 Gbps bidirectional links over up to 20 km of 9/125 µm single-mode fiber. It complies with CSFP MSA Option 2, IEEE 802.3ah 1000BASE-BX20, and SFF-8472, providing two independent bidirectional optical channels (Ch A and Ch B). The 20U version uses a 1310 nm FP laser for TX and 1490 nm PIN RX, while the 20D version uses a 1490 nm DFB laser for TX and 1310 nm PIN RX. Operating from a 3.3 V supply, it supports real-time digital diagnostic monitoring (DDM) and offers hot-pluggable deployment with LC/UPC interface.
| Parameter | Value | Notes |
|---|---|---|
| Data rate | 1.25 Gbps (TX/RX) | IEEE 802.3ah BX20 compliant |
| Reach | 20 km | 9/125 µm SMF |
| TX wavelength | 1310 nm (U) / 1490 nm (D) | FP laser (1310), DFB laser (1490) |
| RX wavelength | 1490 nm (U) / 1310 nm (D) | — |
| TX output power | -9 to -3 dBm | Average |
| Extinction ratio | ≥8.2 dB | — |
| SMSR | ≥30 dB (1490 nm DFB) | — |
| Spectral width | ≤3.5 nm (1310 FP), ≤1 nm (1490 DFB) | — |
| RX sensitivity | ≤-19 dBm | BER ≤1×10⁻¹², ER = 8.2 dB, PRBS 2⁷-1 |
| RX overload | -3 dBm | — |
| LOS assert/de-assert | -38 dBm / -22 dBm; hysteresis 0.5–6 dB | LOS high = signal lost |
| Eye mask | IEEE 802.3ah compliant | Class 1 laser |
| Parameter | Value | Notes |
|---|---|---|
| Supply voltage | 3.13–3.47 V (nom. 3.3 V) | — |
| Max supply current | 450 mA (total for TX+RX) | — |
| Power supply noise | ≤100 mVp-p (100 Hz–1 MHz) | — |
| Case temperature | 0 °C to +70 °C | Operating |
| Connector | LC/UPC | Pluggable |
| Form factor | Compact SFP (CSFP, Option 2) | Hot-pluggable, dual-channel |
| Diagnostics | SFF-8472 DDM (Temp, Vcc, TxBias, TxPower, RxPower) | I²C addresses A0h/A2h (Ch1), B0h/B2h (Ch2) |
| Control/Status | Tx Disable, Tx Fault, LOS | I²C accessible |
At Carritech, we pride ourselves on our exceptional service and commitment to meeting our customers’ needs. Our extensive range of SFP transceivers, including the CT-CSFP-BX-20U, is designed to cater to various requirements, ensuring that you receive the best solutions for your projects. We understand the importance of timely delivery, and our efficient processes are geared towards providing you with the products you need as quickly as possible. Our dedicated team works tirelessly to ensure that your orders are processed and dispatched promptly, so you can rely on us for swift and reliable service.
We recognise that every project is unique, and our flexible approach allows us to adapt to your specific needs. Whether you require immediate delivery or have more complex requirements, we are here to support you every step of the way. Our commitment to customer satisfaction means that we go above and beyond to ensure that you receive your SFP transceivers in a timely manner, without compromising on quality. Trust Carritech to deliver the solutions you need, when you need them.
At Carritech Optics, we stand by the quality and reliability of our optical transceivers. That’s why we proudly offer a lifetime warranty on all products as a testament to our commitment to excellence and customer satisfaction.
Our lifetime warranty provides comprehensive coverage for the entire lifecycle of your optical transceivers, ensuring you experience complete peace of mind when choosing Carritech Optics. The warranty covers:
Should you ever need to make a warranty claim, our team is here to assist you. Simply contact our support team with your product details, and we’ll guide you through a quick and hassle-free process to resolve the issue.
Carritech Optics is dedicated to providing high-quality optical solutions that you can trust for the long haul. With our lifetime warranty, you can confidently invest in our products, knowing that we’re with you every step of the way.
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Find the manufacturer part number you currently use in the list below. Each one has been matched to this Carritech Optics product using the relevant optical specifications and compatibility requirements. Select a part number to view its full details.
Manufacturer part: CSFP-GE-FE-BXU1
Manufacturer part: AT-SPBD20DUAL-13
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