The **KRTB-2152-R** is a specific type of Tri-color (RGB) Light Emitting Diode (LED) commonly used in consumer electronics, automotive interiors, and decorative lighting. It is manufactured by companies like Kingbright. --- ## 1. Core Technical Specifications The KRTB-2152-R is an **SMD (Surface Mount Device)** component. It houses three separate LED chips (Red, Green, and Blue) within a single package. | Parameter | Specification (Typical) | | :--- | :--- | | **Package Size** | 2.1mm x 2.1mm (0808 equivalent) | | **Emitted Colors** | Red (625nm), Green (525nm), Blue (470nm) | | **Forward Voltage ($V_f$)** | R: 2.0V | G: 3.3V | B: 3.3V | | **Forward Current ($I_f$)** | 20mA (per color channel) | | **Luminous Intensity** | R: 120mcd | G: 280mcd | B: 80mcd | | **Viewing Angle** | 120 Degrees | | **Polarity** | Common Anode or Common Cathode (Check Datasheet) | --- ## 2. Pinout and Circuitry To control the KRTB-2152-R, you must address each color channel independently. This allows for color mixing (e.g., turning on Red and Blue to create Purple). ### Basic Wiring Concept ```text (Anode/Cathode) ----> [Resistor] ----> [LED Chip] ----> (Ground/Power) ``` ### Component Structure 1. **Red Die:** Uses AlGaInP material. 2. **Green Die:** Uses InGaN material. 3. **Blue Die:** Uses InGaN material. 4. **Epoxy:** Usually water-clear or diffused to allow for better color blending. --- ## 3. Key Electronic Features * **Color Mixing:** By using **PWM (Pulse Width Modulation)**, you can vary the brightness of each individual chip to produce millions of colors, including white. * **Compact Footprint:** The 2152 package is extremely small, making it ideal for high-density PCBs or backlight arrays. * **Thermal Management:** Because it is an SMD component, the PCB copper traces act as a heatsink. Excessive current without proper resistors will lead to thermal runaway and failure. --- ## 4. Typical Applications * **Backlighting:** LCD displays, switches, and buttons. * **Status Indicators:** Devices that need to show different states (e.g., Green for "Ready", Red for "Error"). * **Wearables:** Smartwatches and fitness trackers due to the low power profile and small size.