1.25G Dual-Port BiDi cSFP 20km Transceiver TX1310/RX1550: 1.25G-cSFP-20-AD

Our EDGEOPTIC 1.25G-cSFP-20-AD is a multi-vendor compatible dual-port compact SFP optical module designed to double port density in Gigabit Ethernet deployments. This cSFP transceiver integrates two independent BiDi (Bidirectional) channels within a single standard SFP footprint, enabling network engineers to maximize rack space utilization while maintaining full Gigabit connectivity over single-mode fiber infrastructure.

The 1.25G-cSFP-20-AD operates with both channels transmitting at 1310nm wavelength and receiving at 1550nm, supporting data rates from 1.063 to 1.25 Gbps per channel. Each channel utilizes BiDi technology with WDM (Wavelength Division Multiplexing) to achieve full-duplex communication over a single fiber strand per port. This module must be paired with its complementary counterpart, the 1.25G-cSFP-20-BD (TX1550/RX1310), to establish proper bidirectional links.

The transceiver employs FP (Fabry-Perot) laser transmitters paired with PIN photodiode receivers for each channel. With transmit power ranging from -9 to -3 dBm and receiver sensitivity of -23 dBm, the module delivers a guaranteed 14 dB optical link budget. This link budget supports transmission distances up to 20 kilometers over standard single-mode fiber, making it suitable for metropolitan access networks and campus backbone applications. However, actual achievable distance depends on fiber plant quality, connector losses, and splice attenuation in the specific installation.

The 1.25G-cSFP-20-AD features a Double LC/UPC connector interface, providing two separate optical ports within the compact housing. The electrical interface conforms to CSFP MSA Option 2 specifications, ensuring compatibility with host equipment designed for compact SFP modules. Our cSFP transceiver can be encoded for compatibility with various equipment platforms from multiple vendors supporting this form factor.

Digital Diagnostic Monitoring (DDM/DOM) functionality is fully supported, providing real-time monitoring of critical parameters including transmitted and received optical power levels for both channels, module temperature, laser bias current, and supply voltage. This diagnostic capability enables proactive network management and simplifies troubleshooting procedures.

The module operates within standard commercial temperature range of 0 to 70°C, suitable for controlled environment installations such as central offices and equipment rooms. Power consumption is managed through a +3.3V single supply rail.

Standards compliance includes IEEE 802.3z for Gigabit Ethernet and IEEE 802.3ah for 1000Base-BX20 applications. The transceiver also supports 1G Fiber Channel at 1.0625 Gbps for storage networking applications. Regulatory certifications include CE marking, RoHS compliance, and Class 1 laser safety ratings per FDA and IEC 60825-1 standards.

Typical deployment scenarios include fiber-to-the-building access networks, enterprise campus backbones, and telecommunications aggregation points where port density optimization is critical. The dual-channel architecture effectively doubles the connectivity options per SFP slot while reducing fiber count through BiDi technology.

Because our focus is providing top quality service, we perform comprehensive quality verification before delivery. This includes optical parameter measurements for both channels, connector cleanliness inspection, and EEPROM memory data validation testing.