The **QBLP679-RK** is a specific surface-mount device (SMD) LED manufactured by **QT-Brightek**. It belongs to the 3228 (1210 metric) package series and is primarily used for status indication and backlighting. --- ### 1. Technical Specifications The following table summarizes the key electrical and optical characteristics of the QBLP679-RK: | Parameter | Specification | | :--- | :--- | | **Emitted Color** | Red | | **Package Size** | 3.2 x 2.8 x 1.9 mm (PLCC-2) | | **Dominant Wavelength** | 620 nm - 630 nm | | **Luminous Intensity (Iv)** | 160 mcd (Typical) @ 20mA | | **Forward Voltage (Vf)** | 2.0V (Typical) / 2.5V (Max) | | **Forward Current (If)** | 20 mA (Standard operating current) | | **Viewing Angle** | 120 Degrees | | **Lens Type** | Water Clear | --- ### 2. Key Internal Components To understand the "electronic parts" of this LED, we look at its construction: * **LED Die (Chip):** The core semiconductor material, typically made of **AlGaInP** (Aluminum Gallium Indium Phosphide) for red high-brightness emission. * **Lead Frame:** The metal structure (usually silver-plated copper) that provides mechanical support and electrical connections (Anode and Cathode). * **Encapsulant:** A clear epoxy or silicone resin that protects the die and helps shape the light output. * **Gold Wire Bond:** A very thin wire that connects the top of the LED chip to the lead frame terminal. --- ### 3. Footprint and Pinout The QBLP679-RK uses a **PLCC-2 package**. It is polarized, meaning it must be installed in the correct orientation to function. * **Cathode (-):** Usually identified by a notch or a "cut corner" on the package body. * **Anode (+):** The opposite terminal. --- ### 4. Circuit Implementation When integrating this part into a circuit, a current-limiting resistor is required. You can calculate the resistor value using Ohm's Law: ```text R = (V_source - V_forward) / I_forward ``` **Example calculation for a 5V supply:** `R = (5V - 2.0V) / 0.02A = 150 Ohms` ---