The **M3A25TBA-R** is a specific part number belonging to a series of **Rotary DIP Switches** manufactured by **Copal Electronics** (now part of Nidec Components). These components are commonly used on Printed Circuit Boards (PCBs) to set configurations or addresses manually. --- ### 1. Component Specification Table | Feature | Specification | | :--- | :--- | | **Component Type** | Rotary DIP Switch | | **Part Number** | M3A25TBA-R | | **Number of Positions** | 10 Positions (Decimal) | | **Output Code** | BCD (Binary Coded Decimal) | | **Actuator Style** | Arrow/Flat (Flush type) | | **Mounting Type** | Surface Mount (SMD / SMT) | | **Packaging** | Tape & Reel (indicated by the "-R") | | **Pin Pitch** | 2.54mm (Standard) | --- ### 2. Electronic Characteristics * **Logic Type:** This is a **Binary Coded Decimal (BCD)** switch. When you rotate the dial to a number (0-9), the internal electrical contacts close in a specific pattern across 4 output pins representing $2^0, 2^1, 2^2,$ and $2^3$. * **Contact Rating:** * *Switching:* Typically 5VDC 100mA. * *Non-Switching:* Typically 50VDC 100mA. * **Sealing:** These parts are usually "process sealed," meaning they can withstand wave soldering and board washing without internal contamination. --- ### 3. Pinout and Coding Logic The switch translates the decimal position on the dial into binary signals. For the **M3A25TBA-R**, the truth table generally follows this logic: | Position | Pin 1 ($2^0$) | Pin 2 ($2^1$) | Pin 4 ($2^2$) | Pin 8 ($2^3$) | | :---: | :---: | :---: | :---: | :---: | | **0** | Open | Open | Open | Open | | **1** | Closed | Open | Open | Open | | **2** | Open | Closed | Open | Open | | **...** | ... | ... | ... | ... | | **9** | Closed | Open | Open | Closed | --- ### 4. Typical Applications * **Address Settings:** Setting unique IDs for nodes in an RS-485 or CAN bus network. * **Mode Selection:** Configuring hardware operation modes (e.g., baud rate selection) without needing a digital interface. * **Industrial Controls:** Used in PLCs and automation modules for field configuration. ---