The **WJM-1GG-R/Q** refers to a high-speed RJ45 connector module, typically used in networking hardware such as switches, routers, and network interface cards (NICs). This part belongs to the **Integrated Connector Module (ICM)** category, meaning it combines a mechanical RJ45 jack with internal magnetic components. --- ### 1. General Specifications The "R/Q" suffix usually denotes specific variations in termination (like press-fit vs. solder) or environmental ratings (RoHS compliance). | Feature | Specification | | :--- | :--- | | **Connector Type** | RJ45 (8P8C) | | **Internal Magnetics** | Included (Transformer + Common Mode Choke) | | **Speed Support** | 10/100/1000 Base-T (Gigabit Ethernet) | | **Orientation** | Right Angle / Side Entry | | **Shielding** | Metal Shield with EMI Tabs | | **LEDs** | Often integrated (usually Green/Yellow) | --- ### 2. Internal Electronic Components Unlike a standard plastic jack, the WJM-1GG-R/Q contains a small PCB inside the housing with several critical electronic parts: #### A. Isolation Transformer * **Purpose:** Provides 1500V AC isolation between the Ethernet cable and the PHY (Physical Layer) chip. * **Function:** Protects sensitive circuitry from static electricity (ESD) and voltage surges on the line. #### B. Common Mode Choke (CMC) * **Purpose:** Noise suppression. * **Function:** Filters out high-frequency electromagnetic interference (EMI) while allowing the differential data signal to pass through. #### C. Bob Smith Termination * **Purpose:** Impedance matching. * **Function:** A network of resistors and capacitors (usually 75Ω resistors and a high-voltage 1000pF capacitor) used to terminate unused wire pairs to ground, reducing crosstalk and EMI. --- ### 3. Pinout and Interface The part typically interfaces between the **Cable Side** (RJ45 pins) and the **PCB Side** (Solder pins). | Side | Description | | :--- | :--- | | **Cable Side** | 8 gold-plated contacts for the Ethernet plug. | | **PCB Side** | 10-12 pins (8 for data signals, 2-4 for integrated LEDs). | | **Shield Tabs** | Grounding points that connect the metal casing to the chassis/earth ground. | --- ### 4. Key Applications * **Networking Gear:** Hubs, Bridges, and high-end Servers. * **Industrial PC:** Ruggedized computers requiring Gigabit speeds. * **IoT Gateways:** Devices requiring a stable, shielded wired connection.