The **FNS-15G-R** is a high-performance **Fiber Optic Transceiver Module** (specifically a 15Gbps SFP+ form factor) typically used in high-speed networking and data storage applications. These modules are designed to convert electrical signals into optical signals (and vice versa) for transmission over fiber optic cables. --- ### 1. Key Technical Specifications The following table outlines the core electronic and optical characteristics of the FNS-15G-R: | Feature | Specification | | :--- | :--- | | **Form Factor** | SFP+ (Small Form-factor Pluggable Plus) | | **Data Rate** | Up to 14.025 Gbps / 15 Gbps | | **Wavelength** | 850 nm (Short Haul) | | **Fiber Type** | Multi-mode Fiber (MMF) | | **Max Distance** | ~35m (OM2), ~100m (OM3), ~150m (OM4) | | **Connector** | Duplex LC | | **Supply Voltage** | 3.3V | | **Power Consumption** | < 1.0W | --- ### 2. Internal Electronic Components The FNS-15G-R consists of several critical sub-assemblies that manage signal integrity: 1. **Optical Transmitter (TOSA):** * Utilizes a **VCSEL** (Vertical-Cavity Surface-Emitting Laser) diode. * Converts high-speed electrical differential signals from the host into light pulses. 2. **Optical Receiver (ROSA):** * Contains a **PIN Photodiode** and a **Transimpedance Amplifier (TIA)**. * Converts incoming light pulses back into electrical signals. 3. **Digital Diagnostics Monitoring (DDM/DOM):** * An internal microprocessor monitors real-time parameters: temperature, supply voltage, laser bias current, and optical transmit/receive power. 4. **EEPROM:** * Contains the module's identification, serial number, and manufacturer data used for compatibility checks with switches (e.g., Cisco, HP, Dell). --- ### 3. Pin Configuration (Electrical Interface) The module interacts with the host PCB via a 20-pin connector. Below are the primary signal groups: ```markdown - Pins 12/13 (RD-/RD+): Receiver Differential Output (Data to Host) - Pins 18/19 (TD-/TD+): Transmitter Differential Input (Data from Host) - Pins 4/5 (SDA/SCL): 2-wire Serial Interface (I2C) for DDM/EEPROM - Pin 2 (TX_Fault): Indicates transmitter malfunctions - Pin 3 (TX_Disable): Turns the laser on or off - Pin 8 (LOS): Loss of Signal indicator (indicates no incoming light) ``` --- ### 4. Applications * **Fibre Channel:** Often used in 16G Fibre Channel (16GFC) storage area networks. * **Ethernet:** High-speed data center switching. * **Storage Arrays:** Connecting servers to high-speed disk arrays.