The **CT0603QWF-R11** is a surface-mount (SMD) Light Emitting Diode (LED) characterized by its small footprint and specific optical properties. It is part of the "0603" series, which is a standard size for miniature electronic components. --- ### 1. Technical Specifications Below are the key electronic and physical characteristics of the CT0603QWF-R11: | Parameter | Specification | | :--- | :--- | | **Package Size** | 0603 (1.6mm x 0.8mm) | | **Color** | White (High Brightness) | | **Forward Voltage ($V_F$)** | Typically 2.8V - 3.2V | | **Forward Current ($I_F$)** | 20mA (Standard operating current) | | **Luminous Intensity** | Varies by bin (typically 180-450 mcd) | | **Viewing Angle** | 120° - 140° | | **Lens Type** | Water Clear / Yellow Diffused (Phosphor coat) | --- ### 2. Part Number Breakdown Understanding the nomenclature helps in identifying the component's role: * **CT**: Manufacturer series prefix (often associated with Central Technologies or CML Innovative Technologies). * **0603**: The EIA package size (1.6mm length x 0.8mm width). * **QWF**: Denotes the color spectrum and material (White / InGaN technology). * **R11**: Usually refers to the specific reel packaging or a revision code for the internal chip brightness binning. --- ### 3. Electronic Design Considerations #### Resistor Calculation When integrating this LED into a circuit, you must use a current-limiting resistor to prevent burnout. ```python # Formula: R = (V_source - V_forward) / I_forward V_source = 5.0 # Example 5V supply V_forward = 3.1 # Typical for White LED I_forward = 0.02 # 20mA Resistance = (5.0 - 3.1) / 0.02 print(f"Required Resistor: {Resistance} Ohms") # Result: 95 Ohms (Use 100 Ohm standard resistor) ``` #### Polarity and Mounting * **Anode/Cathode:** As a diode, it is polarity sensitive. The cathode is usually marked with a green stripe or a notch on the underside of the SMD package. * **Reflow Soldering:** Designed for automated SMT (Surface Mount Technology) assembly using Lead-Free reflow profiles. --- ### 4. Common Applications * **Backlighting:** Used for LCD screens, push buttons, and switches. * **Status Indicators:** Low-power indicators for consumer electronics (laptops, routers). * **Automotive:** Internal dashboard lighting and console accents. ---