The **RJ11-4LC2-R** is a specific surface-mount (SMT) modular jack designed for telecommunications and data networking applications. It is manufactured by various electronic component brands (often following industry-standard footprints like those from **Pulse Electronics** or **Amphenol**). ### 1. General Specifications This part is a 4-position, 2-contact (4P2C) right-angle connector. | Feature | Specification | | :--- | :--- | | **Connector Type** | RJ11 Modular Jack | | **Positions/Contacts** | 4 Positions / 2 Contacts (4P2C) | | **Mounting Type** | Surface Mount (SMT) / Right Angle | | **Shielding** | Unshielded | | **Orientation** | Side Entry (Right Angle) | | **Standard Compliance** | RoHS Compliant | --- ### 2. Physical & Mechanical Characteristics The "4LC2" in the part number typically denotes the configuration of the internal wiring and physical layout: * **Housing Material:** High-temperature thermoplastic (usually LCP or Nylon), designed to withstand reflow soldering temperatures. * **Contact Material:** Phosphor Bronze with Gold plating over Nickel. Gold plating (often 6u" to 50u") is used to prevent corrosion and ensure low contact resistance over time. * **Tab Direction:** Usually "Tab Down" or "Tab Up" depending on the specific series, allowing for easy insertion and removal of the RJ11 plug. * **Solder Pads:** Designed with side-wing pads for mechanical stability on the PCB to prevent the connector from being ripped off during cable insertion. --- ### 3. Electrical Characteristics These parts are designed for low-voltage signal transmission, typical of telephony or low-speed serial data. | Parameter | Typical Value | | :--- | :--- | | **Current Rating** | 1.5 Amps | | **Voltage Rating** | 125 VAC | | **Insulation Resistance** | 500 MΩ Min | | **Contact Resistance** | 20 mΩ Max | | **Dielectric Strength** | 1000 VAC RMS (60Hz/1min) | --- ### 4. Application Use Cases Because it is a **4P2C** configuration (4 positions but only 2 pins loaded with copper), it is most commonly used for: * **Landline Telephones:** Connecting a single phone line. * **Modems:** Low-speed dial-up or DSL equipment. * **Industrial Control:** Used as a low-cost serial port (RS-232/RS-485 over RJ11) for programming or sensors. * **Consumer Electronics:** Security systems and POS terminals. --- ### 5. Technical Footprint (Simplified) When designing a PCB for this part, engineers must account for the SMT pads and the plastic locating pegs (bosses). ```text [ RJ11 JACK TOP VIEW ] _______________________ | | | [P1] [P2] [P3] [P4] | <-- 4 Positions | | | | | | | (NC) (CU) (CU) (NC) | <-- Only 2 loaded with copper |_______________________| | | [SMT PAD] [SMT PAD] <-- Side anchors for stability ``` ---