The **M2REB-RDA-R** is a specific part number typically associated with the **M2 Series** of miniature rotary switches, often manufactured by companies like **NKK Switches**. These are designed for logic-level applications where space is at a premium. --- ## 1. Part Number Breakdown Understanding the electronic characteristics begins with decoding the nomenclature: | Component Segment | Description | Meaning | | :--- | :--- | :--- | | **M2** | Series | Miniature Process Sealed Rotary | | **REB** | Actuator & Terminals | PC Terminals / Screwdriver Actuator | | **RDA** | Circuitry/Positions | Binary Coded Decimal (BCD) - 10 Positions | | **-R** | Packaging/RoHS | Typically indicates RoHS compliance or Tape & Reel | --- ## 2. Key Electronic Specifications The M2REB-RDA-R is built for low-power signal switching rather than power distribution. * **Switching Type:** Binary Coded Decimal (BCD). The output changes based on the position (0–9), providing a 4-bit binary output. * **Electrical Capacity:** * **Logic Level:** 100mA @ 5V DC. * **Max Voltage/Current:** Usually rated up to 0.4VA maximum at 28V AC/DC maximum. * **Contact Resistance:** Typically less than 100 milliohms. * **Insulation Resistance:** 1,000 Megohms minimum at 250V DC. * **Dielectric Strength:** 250V AC minimum between contacts for at least one minute. --- ## 3. Physical & Material Composition The internal electronic parts are protected by a "Process Sealed" construction, allowing the part to withstand automated soldering and washing. ### Internal Components: * **Contacts:** Usually **Gold-plated** over Nickel or Brass. Gold is used because these switches operate at very low currents where oxidation would otherwise prevent a clean signal. * **Base/Housing:** High-temperature glass-reinforced polyamide or liquid crystal polymer (LCP) to resist soldering heat. * **Rotor:** Internal rotating disc that bridges the common pin to the specific binary output pins (1, 2, 4, 8). --- ## 4. Truth Table (BCD Output) As a **BCD** switch, the electronic behavior follows this logic pattern across its pins: | Position | Pin 1 (1) | Pin 2 (2) | Pin 3 (4) | Pin 4 (8) | | :---: | :---: | :---: | :---: | :---: | | **0** | Off | Off | Off | Off | | **1** | **ON** | Off | Off | Off | | **3** | **ON** | **ON** | Off | Off | | **7** | **ON** | **ON** | **ON** | Off | | **9** | **ON** | Off | Off | **ON** | --- ## 5. Common Applications * **Address Setting:** Setting IDs for devices on a BUS (like RS-485 or CAN). * **Configuration:** Selecting modes on a PCB without needing a display or software interface. * **Industrial Controls:** Used in compact PLC modules or handheld test equipment.