The **NDV-0C20-R** is a high-precision, low-profile **Rotary DIP Switch** manufactured by **DiPTronics**. These components are primarily used on Printed Circuit Boards (PCBs) to set binary-coded configurations or addresses for electronic devices. --- ## Technical Specifications The following table summarizes the key electrical and physical characteristics of the NDV-0C20-R: | Feature | Specification | | :--- | :--- | | **Manufacturer** | DiPTronics Manufacturing Inc. | | **Switch Type** | Rotary DIP Switch | | **Actuator Type** | Flush / Flat (Requires screwdriver to turn) | | **Number of Positions** | 10 Positions (0-9) | | **Code Type** | BCD (Binary Coded Decimal) | | **Mounting Type** | Surface Mount (SMT/SMD) | | **Contact Rating** | 100mA at 50V DC (Static) / 25mA at 24V DC (Switching) | | **Operating Force** | 200 gf·cm max | | **Operating Temp** | -25°C to +85°C | --- ## Key Design Components ### 1. The BCD Encoding The "0C" in the part number indicates **BCD (Real Code)**. This means the switch has 4 output pins representing bits $2^0, 2^1, 2^2, \text{and } 2^3$. When you rotate the dial to a decimal number (0-9), the internal contacts close in a specific pattern to create the binary equivalent. ### 2. Physical Construction * **Gold-Plated Contacts:** Ensures high reliability and prevents oxidation over time, which is critical for low-voltage logic circuits. * **Sealed Structure:** The "V" in the series often denotes a sealed construction (washable), allowing the PCB to be cleaned after soldering without damaging the internal switch mechanism. * **Flat Actuator:** The "Flush" design ensures the switch does not snag on other components or the device housing; it typically requires a small flathead screwdriver to adjust. ### 3. Application Use Cases * **Address Setting:** Used in industrial automation (RS-485 or CAN bus nodes) to give each device a unique ID. * **Configuration:** Setting baud rates, mode selection, or hardware overrides on embedded systems. * **Internal Options:** Selecting jumper-like settings without needing physical jumpers. --- ## Circuit Layout Example When integrating this into a schematic, the Common (C) pin is usually tied to Ground (GND), and the four output pins are connected to a Microcontroller (MCU) with internal pull-up resistors enabled. ```c // Pseudo-code for reading the NDV-0C20-R state int bcd_val = (digitalRead(PIN_D) << 3) | (digitalRead(PIN_C) << 2) | (digitalRead(PIN_B) << 1) | digitalRead(PIN_A); ```