The **C4SMC-RGF** is a high-brightness, through-hole LED manufactured by **Cree LED** (formerly Cree Inc.). It is specifically designed for outdoor video screens, digital signage, and variable-message signs. --- ### 1. Key Technical Specifications The following table highlights the primary electronic and optical characteristics of the C4SMC-RGF: | Parameter | Specification | | :--- | :--- | | **Color** | Red | | **Dominant Wavelength** | 619nm - 624nm | | **Luminous Intensity** | 770 mcd (min) - 2130 mcd (max) | | **Viewing Angle** | 70° Horizontal / 35° Vertical (Oval) | | **Forward Current ($I_F$)** | 50 mA (Maximum) | | **Forward Voltage ($V_F$)** | 2.1V (Typical) / 2.6V (Maximum) | | **Lens Type** | Tinted, Diffused (Oval shape) | | **Mounting Type** | Through-Hole (Radial) | --- ### 2. Physical Design Features * **Oval Shape:** Unlike standard round LEDs, the C4SMC series has an oval lens. This is engineered to provide a wide horizontal viewing angle and a narrow vertical viewing angle, which is ideal for outdoor displays where viewers are usually at eye level or below the screen. * **Standoffs:** The leads often include "standoffs" (small bumps on the wire) to ensure the LED sits at a consistent height above the PCB during the soldering process. * **Epoxy Material:** The lens is made of an optical-grade epoxy that contains UV inhibitors to prevent yellowing or degradation when exposed to direct sunlight for long periods. --- ### 3. Electronic Behavior & Circuit Considerations When integrating the C4SMC-RGF into a circuit, consider these electrical factors: #### Current Regulation Because LEDs are current-driven devices, you must use a current-limiting resistor or a constant-current LED driver. * **Example Calculation:** To run the LED at 20mA from a 5V supply: `R = (V_supply - V_forward) / I_forward` `R = (5V - 2.1V) / 0.02A = 145 Ohms` #### Reverse Voltage This LED has a maximum reverse voltage ($V_R$) of **5V**. Exceeding this value can cause immediate permanent damage to the semiconductor junction. --- ### 4. Common Applications * **Full-Color Outdoor Video Screens:** Used as the "Red" component in an RGB pixel. * **Variable Message Signs (VMS):** Highway traffic alerts and speed limit signs. * **Petrol Station Price Signs:** High-visibility outdoor numeric displays. * **Advertising Billboards:** Large-scale digital signage.