The **SML-R13UWT86P** is a high-brightness surface-mount (SMD) Light Emitting Diode (LED) manufactured by **ROHM Semiconductor**. It belongs to the SML-R13 series, which is characterized by its compact "0603" size and high reliability. --- ### 1. Key Technical Specifications Below are the primary electronic and physical characteristics of the SML-R13UWT86P: | Feature | Specification | | :--- | :--- | | **Package Size** | 1608 Metric (0603 Inch) | | **Emitting Color** | Red | | **Luminous Intensity** | 25 mcd to 63 mcd (at 20mA) | | **Forward Voltage ($V_F$)** | 2.0 V (Typical) | | **Forward Current ($I_F$)** | 20 mA | | **Wavelength ($\lambda_D$)** | 624 nm | | **Operating Temperature** | -40°C to +85°C | | **Lens Type** | Transparent / Clear | --- ### 2. Internal Composition and Materials The performance of this LED is determined by its internal semiconductor structure: * **Chip Material:** It typically utilizes **AlGaInP** (Aluminum Gallium Indium Phosphide) technology. This material is chosen for red LEDs because it provides high efficiency and brightness compared to older GaAsP technologies. * **Form Factor:** The "R13" designation refers to the ultra-compact mold, measuring approximately **1.6mm x 0.8mm**. * **Termination:** The device features gold (Au) or tin (Sn) plated terminals (depending on specific batch coding) designed for reflow soldering. --- ### 3. Electrical Performance Considerations When integrating the SML-R13UWT86P into a circuit, keep the following electrical behaviors in mind: 1. **Polarity:** As a diode, it only conducts in one direction. The cathode is usually marked with a notch or a green mark on the bottom of the package. 2. **Power Dissipation:** The maximum power dissipation is generally around **48mW**. Exceeding this will lead to thermal runaway and component failure. 3. **Current Limiting:** A resistor must be used in series. * *Calculation Example:* To run on a 5V rail: $R = (5V - 2.0V) / 0.02A = 150 \Omega$. --- ### 4. Applications Due to its small footprint and standard red emission, it is commonly used in: * **Status Indicators:** Power-on lights for portable electronics. * **Backlighting:** Small LCD screens or membrane switches. * **Automotive:** Internal dashboard illumination and buttons.