The **M2REB-R2A-R/Q** refers to a high-performance **PCIe M.2 to Dual-Port Gigabit Ethernet (GbE)** network adapter module, typically utilizing an Intel controller. These parts are commonly used in industrial computing, embedded systems, and compact servers where space is limited but high-speed networking is required. --- ### 1. Key Electronic Components & Specifications The module is designed around a specific architecture to bridge the PCIe bus to Ethernet physical layers. | Component / Feature | Specification Details | | :--- | :--- | | **Main Controller** | Typically **Intel® I210-IT/AT** or **I350-AM2** (depending on the specific revision) | | **Interface Type** | M.2 B+M Key (utilizing PCIe v2.1 x1 or x2) | | **Network Speed** | 10/100/1000 Mbps (Gigabit Ethernet) | | **Port Count** | Dual RJ45 Ports (usually via a daughterboard/header) | | **Power Consumption** | Approx. 1.5W to 2.5W | | **Operating Temperature** | Commercial (0°C to 70°C) or Industrial (-40°C to 85°C) | --- ### 2. Functional Architecture The electronic design consists of three primary stages: #### A. The M.2 Interface (Input) This section connects to the host motherboard. It handles the **PCI Express (PCIe)** signaling. It includes: * **Differential Pairs:** High-speed lanes for data transmission. * **Clock Signals:** REFCLK+/- for synchronization. * **Power Management:** Conversion of 3.3V from the M.2 slot to the specific core voltages required by the Intel chip. #### B. The Intel Ethernet Controller (Processing) This is the "brain" of the module. It handles: * **MAC (Media Access Control):** Manages data framing and addressing. * **PHY (Physical Layer):** Converts digital data into analog signals suitable for copper cables. * **Buffer Memory:** Integrated SRAM for packet queuing to prevent data loss. #### C. The Isolation Transformers & RJ45 (Output) Since Ethernet involves long copper cables, electronic isolation is critical: * **Magnetics (Transformers):** Protect the internal circuitry from electrostatic discharge (ESD) and voltage surges. * **LED Controllers:** Drivers for the "Link" and "Activity" indicators. --- ### 3. Pinout & Connectivity The "R/Q" designation often refers to the cabling orientation or the specific connector type used to link the M.2 PCB to the external RJ45 bracket. ```yaml Pin Configuration Categories: - PCIe Lanes: Lane 0 (TX/RX), Lane 1 (TX/RX) - Power: 3.3V, GND - SMBus: For management/monitoring (optional) - Sideband: Configurable I/O for LED status or Wake-on-LAN (WoL) ``` --- ### 4. Typical Use Cases * **Industrial PC (IPC):** Adding redundant LAN ports for automation. * **Network Appliances:** Small form factor firewalls or routers. * **Digital Signage:** High-reliability connectivity for remote management.