The **KRTB-2C2-R/Q** is a high-performance, surface-mount (SMD) **Tri-color RGB LED** manufactured by ROHM Semiconductor. It is specifically designed for high-density mounting and superior color mixing, commonly used in full-color displays and indicator panels. --- ### 1. Key Technical Specifications | Parameter | Specification | |:---|:---| | **LED Colors** | Red, Green, Blue (RGB) | | **Package Size** | 1010 (1.0 x 1.0 mm) | | **Configuration** | Common Anode | | **Luminous Intensity (Red)** | ~25 - 56 mcd @ 5mA | | **Luminous Intensity (Green)** | ~56 - 140 mcd @ 5mA | | **Luminous Intensity (Blue)** | ~14 - 36 mcd @ 5mA | | **Forward Voltage (Typ)** | R: 1.9V | G: 2.8V | B: 2.8V | | **Operating Temperature** | -40°C to +85°C | --- ### 2. Internal Structure and Pinout The device integrates three separate LED chips into a single ultra-miniature package. By controlling the current flowing through each chip, you can achieve a wide spectrum of colors, including white. * **Common Anode (+) :** The positive terminals of all three LEDs are connected internally to a single pin. * **Individual Cathodes (-) :** Each color (R, G, B) has its own negative terminal, allowing independent brightness control via Pulse Width Modulation (PWM). --- ### 3. Core Electronic Features * **Miniaturization:** The 1.0mm x 1.0mm footprint allows for an extremely fine pixel pitch, making it ideal for high-resolution indoor LED screens. * **Black Package Base:** The housing is typically black-faced to improve contrast levels in display applications, reducing reflections from ambient light. * **Low Power Consumption:** Optimized to operate at low forward currents (typically 5mA), reducing heat dissipation in dense arrays. * **Color Uniformity:** ROHM utilizes precision sorting to ensure that the wavelength and brightness are consistent across different batches. --- ### 4. Circuit Implementation Example To drive this LED using a microcontroller (like an Arduino or ESP32), you generally use current-limiting resistors for each cathode. ```cpp // Example: Setting a custom color via PWM int redPin = 9; // Connect to Red Cathode int greenPin = 10; // Connect to Green Cathode int bluePin = 11; // Connect to Blue Cathode void setup() { pinMode(redPin, OUTPUT); pinMode(greenPin, OUTPUT); pinMode(bluePin, OUTPUT); } void loop() { // Common Anode: Low value (0) = Brightest, High value (255) = OFF analogWrite(redPin, 150); analogWrite(greenPin, 200); analogWrite(bluePin, 50); } ``` --- ### 5. Common Applications * **High-Resolution Displays:** Indoor LED billboards and video walls. * **Consumer Electronics:** Status indicators for smartphones, wearables, and laptops. * **Gaming Peripherals:** RGB lighting for keyboards and mice where space is limited. * **Automotive Interior:** Small-scale ambient lighting and dashboard icons.