The **SML-R12M8T** is a high-brightness, surface-mount (SMD) Light Emitting Diode (LED) manufactured by **ROHM Semiconductor**. It belongs to the Mini-Mold SML-R12 series, characterized by its compact size and high reliability. --- ## 1. Technical Specifications The following table summarizes the core electrical and optical characteristics of the SML-R12M8T: | Parameter | Value / Specification | | :--- | :--- | | **Color** | Yellowish-Green (MG) | | **Wavelength ($\lambda_D$)** | 572 nm (Typical) | | **Luminous Intensity ($I_V$)** | 25 mcd (at 20mA) | | **Forward Voltage ($V_F$)** | 2.2 V (Typical) | | **Forward Current ($I_F$)** | 20 mA (Max Continuous) | | **Operating Temperature** | -40°C to +85°C | | **Package Size** | 1608 (0603 inch) - 1.6 x 0.8 mm | | **Lens Type** | Transparent (Clear) | --- ## 2. Key Electronic Features ### A. Material Composition The SML-R12M8T utilizes **GaP (Gallium Phosphide)** as the base semiconductor material. GaP is standard for producing green and yellow-green spectrums efficiently at low power. ### B. Package Design (1608 Metric) The "R12" designation refers to the chip-LED structure. It is an **0603 (inch)** footprint, which is one of the most common sizes for indicator lights. Its low profile (0.55mm height) makes it ideal for thin consumer electronics. ### C. Thermal and Electrical Robustness * **Power Dissipation ($P_D$):** Rated at 75mW. * **Peak Forward Current:** Can handle up to 100mA for very short pulses (duty 1/10, 1ms). * **Reverse Voltage ($V_R$):** Rated at 5V, meaning it requires protection circuits if used in AC or high-noise environments. --- ## 3. Recommended Circuit Configuration When integrating this LED into a circuit, a current-limiting resistor is mandatory to prevent thermal runaway. ### Calculation Example: To run the LED from a **5V DC source** at a safe **10mA**: ```text R = (V_source - V_F) / I_F R = (5V - 2.2V) / 0.01A R = 280 Ohms (Use a standard 300Ω or 330Ω resistor) ``` --- ## 4. Typical Applications Due to its yellowish-green hue and small form factor, it is commonly used for: * **Status Indicators:** Power ON/OFF lights on PCBs. * **Backlighting:** Small LCD screens or membrane switches. * **Consumer Electronics:** Wearables, smart home devices, and mobile handsets. * **Automotive:** Internal dashboard lighting and button illumination.