The **KWMS2-FB-R** is an electronic component commonly categorized as a **Bi-Color Surface Mount (SMD) LED indicator**. These components are frequently used in consumer electronics, automotive dashboards, and industrial control panels to provide visual feedback. Below is a detailed breakdown of its technical specifications and electronic properties. --- ## 1. Technical Specifications The KWMS2-FB-R is typically a two-color chip LED (often Red and Blue or Green depending on the specific batch configuration, though "R" usually denotes a Red primary). | Feature | Specification (Typical) | | :--- | :--- | | **Mounting Type** | Surface Mount Device (SMD) | | **Package Size** | 0603 or 0805 (Metric 1608/2012) | | **Colors** | Bi-Color (e.g., Red / Blue or Red / Green) | | **Lens Type** | Water Clear / Transparent | | **Configuration** | Common Anode or Common Cathode | | **Operating Temperature** | -40°C to +85°C | --- ## 2. Electrical Characteristics To operate these parts safely, specific electrical parameters must be observed. ### Forward Voltage ($V_F$) The voltage required to illuminate the LED varies by color: * **Red:** ~1.8V to 2.2V * **Blue/Green:** ~3.0V to 3.4V ### Forward Current ($I_F$) * **Nominal:** 20mA * **Peak (Pulse):** Up to 100mA (with specific duty cycles) ### Luminous Intensity This measures the brightness (measured in millicandela, mcd). The brightness is proportional to the current supplied, but efficiency drops at very high currents. --- ## 3. Pin Configuration and Circuitry Because this is a **Bi-Color** LED, it typically has 3 or 4 terminals. 1. **3-Pin Type:** Usually shares a common pin (Anode or Cathode). By powering one of the two outer pins, you get a single color. Powering both creates a blended third color (e.g., Red + Blue = Purple). 2. **4-Pin Type:** Provides independent control for both internal LED chips, allowing for more complex pulse-width modulation (PWM) color mixing. ### Typical Application Circuit When connecting the KWMS2-FB-R to a microcontroller (like an Arduino or ESP32), current-limiting resistors are mandatory. ```cpp // Example: Calculating Resistor Value (R) // R = (Source Voltage - Forward Voltage) / Desired Current // For 5V supply and Red LED (2V): // (5V - 2V) / 0.020A = 150 Ohms ``` --- ## 4. Key Applications * **Status Indicators:** Showing power "On" (Blue) or "Error" (Red). * **Backlighting:** Illuminating buttons on a control interface. * **Network Equipment:** Indicating data transmission or link status on routers and switches.