## Technical Overview of SML-R12YTT87P The **SML-R12YTT87P** is a high-brightness Surface Mount Device (SMD) LED manufactured by **ROHM Semiconductor**. It belongs to the SML-R12 series and is commonly used for status indication in consumer electronics and industrial equipment. ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Color** | Yellow | | **Luminous Intensity** | 40 mcd (typical) | | **Dominant Wavelength** | 590 nm | | **Forward Voltage ($V_F$)** | 2.0 V (typical) | | **Forward Current ($I_F$)** | 20 mA (standard operating current) | | **Operating Temperature** | -40°C to +85°C | | **Package Size** | 0603 (1608 Metric) | | **Dimensions** | 1.6 x 0.8 mm (Thickness: 0.36 mm) | --- ### 2. Physical Construction and Form Factor * **Ultra-Thin Profile:** The "R12" series is characterized by its extremely low profile (0.36mm thickness). This makes it ideal for thin devices like smartphones, wearables, and membrane switches. * **Material:** It typically utilizes **AlGaInP** (Aluminium Gallium Indium Phosphide) technology, which provides high brightness and efficiency for yellow/orange/red spectrums. * **Package Type:** 0603 SMD. The bottom of the device features gold-plated electrodes for high reliability and protection against corrosion. --- ### 3. Electrical Characteristics & Usage To integrate this part into a circuit, you must calculate the appropriate current-limiting resistor to prevent damage. #### Calculation Example: If using a 5V power supply: ```text R = (V_supply - V_forward) / I_forward R = (5V - 2.0V) / 0.02A R = 150 Ohms ``` #### Key Features: 1. **High Reliability:** Designed to withstand standard reflow soldering temperatures. 2. **Polarity:** The cathode is usually marked with a green notch or mark on the bottom side of the package. 3. **Efficiency:** Optimized for low power consumption while maintaining visible brightness even in well-lit environments. --- ### 4. Common Applications * **Backlighting:** Keypads, LCDs, and switches. * **Indicators:** Power-on status, battery level indicators, or error signals. * **Automotive:** Internal dashboard lighting (where AEC-Q101 qualified versions are available).