The **AA4040ZGSK** is a high-performance Surface Mount (SMD) Light Emitting Diode (LED) manufactured by Kingbright. It is specifically a **Right-Angle (Side-Looking)** LED, which means it emits light parallel to the PCB surface rather than perpendicular to it. --- ### 1. Key Technical Specifications Below are the primary electrical and optical characteristics for the AA4040ZGSK: | Parameter | Value | | :--- | :--- | | **Emitting Color** | Green | | **Material** | InGaN (Indium Gallium Nitride) | | **Package Size** | 4.0mm x 4.0mm x 1.2mm | | **Forward Voltage ($V_F$)** | 3.3V (Typical) / 4.1V (Max) | | **Forward Current ($I_F$)** | 30mA (Max Continuous) | | **Luminous Intensity ($I_v$)** | 500 - 1000 mcd @ 20mA | | **Wavelength ($\lambda_d$)** | 525 nm (True Green) | | **Viewing Angle** | 120° | | **Lens Type** | Water Clear | --- ### 2. Physical Design and Dimensions The "AA4040" prefix refers to the physical footprint of the component. * **Form Factor:** 4.0mm x 4.0mm square base. * **Orientation:** It is a **Right-Angle LED**. This design is critical for edge-lighting applications or status indicators on the side of a device casing. * **Mounting:** Designed for automated SMT (Surface Mount Technology) assembly and is compatible with infrared reflow soldering. --- ### 3. Electronic Behavior and Circuit Integration To integrate this part into an electronic circuit, it is essential to calculate the appropriate current-limiting resistor to prevent damage. #### Resistance Calculation Example If using a 5V power supply: ```python # Ohms Law: R = (V_supply - V_forward) / I_target # V_supply = 5V # V_forward = 3.3V # I_target = 0.02A (20mA) R = (5 - 3.3) / 0.02 R = 85 Ohms # Use a standard 100 Ohm resistor for safety ``` ### 4. Typical Applications * **Backlighting:** Ideal for LCD displays or membrane switches. * **Edge Indicators:** Used on the edges of PCBs to shine through holes in a plastic enclosure. * **Consumer Electronics:** Power status lights on laptops, routers, and handheld devices. * **Optical Encoding:** Used in sensors where side-firing light is required for a compact footprint. ---