The **M3R24TCJ-R** is a specific part number belonging to a series of **Rotary Coded Switches** manufactured by companies like Copal Electronics (Nidec). These components are used to manually set binary or hexadecimal values on a circuit board. --- ### 1. Key Technical Specifications The part number encodes specific characteristics regarding its orientation, coding, and packaging. | Feature | Specification | | :--- | :--- | | **Component Type** | Rotary Coded Switch | | **Code Type** | Binary Coded Decimal (BCD) or Hexadecimal (depending on specific variant) | | **Number of Positions** | 10 (BCD) or 16 (Hex) | | **Mounting Type** | Surface Mount (SMD / Gull-wing) | | **Actuator Style** | Flush (requires screwdriver to turn) | | **Orientation** | Top Actuated | | **Contact Rating** | Typically 100mA at 5V DC (switching) | | **Packaging** | Tape and Reel ("-R" suffix) | --- ### 2. Functional Breakdown #### A. Internal Switching Logic The switch translates the physical position of the rotor into a digital output. For a **10-position (BCD)** switch, it provides 4 output pins representing bits (1, 2, 4, 8). * **Position 0:** All outputs open. * **Position 9:** Outputs 1 and 8 are closed (active). #### B. Material and Durability * **Contacts:** Usually gold-plated to prevent oxidation and ensure low contact resistance over time. * **Housing:** High-temperature plastic (PPS or LCP) capable of withstanding lead-free reflow soldering temperatures. * **Sealing:** These parts are often "washable," meaning they are sealed with an O-ring or tape to allow board washing after soldering without contaminating the contacts. --- ### 3. Connection Diagram (General Concept) The footprint typically consists of a Common (C) pin and four output pins representing the binary weighting. ```markdown [ 1 ] (Bit 1) [ 2 ] (Bit 2) [ C ] [ ] (Common) [ 4 ] (Bit 4) [ 8 ] (Bit 8) ``` --- ### 4. Common Applications * **Industrial Controls:** Setting Modbus or CAN bus node IDs. * **Telecommunications:** Configuring hardware addresses on rack-mounted cards. * **Peripherals:** Selecting operation modes (e.g., baud rate or frequency) without needing a digital interface or display. ---