Specifications
The 25Gbps Bi-Directional SFP28 Transceiver is designed for high-speed data transmission over single-mode fiber (SMF) for distances up to 40 kilometers. This module supports data rates from 24.33Gbps to 25.78Gbps and features two configurations: CT-SFP28-BX-40U, which uses a 1270nm DML laser for transmission and a 1310nm APD receiver, and CT-SFP28-BX-40D, which transmits at 1310nm and receives at 1270nm. Compliant with SFP28 MSA, SFF-8431, and SFF-8472 standards, it is suitable for applications such as 25GE BASE-LR Ethernet and CPRI Option 10/eCPRI.
Operating on a single +3.3V power supply with power consumption below 1.5W, the transceiver is energy-efficient and available in both commercial (0°C to 70°C) and industrial (-40°C to 85°C) temperature ranges. It features a compact, hot-pluggable design with an LC single connector for seamless integration. The transmitter delivers an average output power of 0dBm to +6dBm with an extinction ratio of 3.5dB, while the receiver provides sensitivity down to -19dBm. Advanced features such as Loss of Signal (LOS) detection and digital diagnostic monitoring enable real-time tracking of key parameters like temperature, voltage, bias current, and optical power, ensuring reliable performance and ease of maintenance.
These hot-pluggable modules support data rates from 24.33 to 25.78 Gbps and comply with IEEE 802.3cc, SFP28 MSA, SFF-8431, and SFF-8432 standards. They operate over single-mode fiber with a simplex LC connector: BX-40U transmits at 1270 nm and receives at 1310 nm, while BX-40D transmits at 1310 nm and receives at 1270 nm. With a 40 km reach, APD/TIA receivers, and integrated CDR, they deliver high sensitivity and low jitter performance. Power consumption is <1.5 W on a single 3.3 V supply, with commercial (0 °C to +70 °C) and industrial (−40 °C to +85 °C) temperature options. Digital diagnostics monitoring (DDMI) provides real-time reporting of key parameters.
Key Parameters
| Specification | CT-SFP28-BX-40U | CT-SFP28-BX-40D | Notes |
|---|---|---|---|
| Form factor / connector | SFP28 (hot-pluggable), LC simplex | SFP28 (hot-pluggable), LC simplex | Single-fiber bidirectional |
| Data rate | 24.33 – 25.78 Gbps | 24.33 – 25.78 Gbps | Rate adaptation supported |
| Reach | Up to 40 km SMF | Up to 40 km SMF | — |
| Tx wavelength | 1270 nm | 1310 nm | DML laser |
| Rx wavelength | 1310 nm | 1270 nm | APD/TIA receiver |
| Tx optical power | 0 to +6 dBm | 0 to +6 dBm | Average |
| Extinction ratio | ≥ 3.5 dB | ≥ 3.5 dB | — |
| Spectral width | ≤ 1 nm | ≤ 1 nm | — |
| Side-mode suppression | ≥ 30 dB | ≥ 30 dB | — |
| Tx off power | ≤ –30 dBm | ≤ –30 dBm | — |
| Receiver sensitivity | ≤ –19 dBm (OMA) | ≤ –19 dBm (OMA) | BER ≤ 5 × 10⁻⁵ |
| Receiver overload | −5 dBm max | −5 dBm max | — |
| Receiver reflectance | ≤ –12 dB | ≤ –12 dB | — |
| LOS assert/de-assert | −35 dBm / −21 dBm | −35 dBm / −21 dBm | 0.5 dB hysteresis |
| Supply voltage | 3.14 – 3.46 V | 3.14 – 3.46 V | Single 3.3 V supply |
| Power consumption | <1.5 W | <1.5 W | — |
| Diagnostics | Temp., bias, Tx/Rx power, Vcc | Temp., bias, Tx/Rx power, Vcc | Digital diagnostics (DDMI) |
| Operating case temp. | 0 °C to +70 °C (commercial), −40 °C to +85 °C (industrial) | Same | — |
| Compliance | IEEE 802.3cc, SFP28 MSA, SFF-8431/8432, RoHS, EN 60825 Class 1 | Same | Standards compliant |
