The **QTLP673C-R** is a specific surface-mount (SMD) Light Emitting Diode (LED) produced by ON Semiconductor (formerly Fairchild). It is part of the subminiature chip LED series, designed for small-scale electronic indicator applications. --- ### ## Technical Specifications The following table summarizes the key electrical and optical characteristics of the QTLP673C-R: | Parameter | Specification | | :--- | :--- | | **Color** | Red | | **Wavelength (Peak)** | 630 nm | | **Luminous Intensity** | 1.0 mcd (Typical) | | **Forward Voltage (Vf)** | 2.0V (Typical) / 2.8V (Max) | | **Forward Current (If)** | 20 mA | | **Viewing Angle** | 50 degrees | | **Package Style** | 0805 (Metric 2012) | | **Lens Type** | Water Clear | --- ### ## Internal Construction and Chemistry The device is built using **AlGaAs (Aluminum Gallium Arsenide)** on a GaAs substrate. This material composition is what provides the high efficiency and the specific red wavelength. ### ### Key Physical Features: 1. **Substrate:** Provides the mechanical base for the semiconductor die. 2. **Epoxy Encapsulation:** A clear epoxy protects the die and shapes the light beam. 3. **Solder Pads:** Located on the bottom of the package for surface mount soldering (SMT). --- ### ## Application and Usage Because of its small footprint (0805 size), the QTLP673C-R is used primarily in space-constrained environments: * **Status Indicators:** Power-on lights for consumer electronics (laptops, routers). * **Backlighting:** Illuminating small LCD screens or push-button switches. * **Medical Devices:** Compact diagnostic equipment interfaces. * **Automotive:** Dashboard indicators and internal accent lighting. --- ### ## Comparison with Similar LEDs When selecting this part, it is often compared based on its "Clear" vs. "Diffused" lens. | Part Number | Lens Type | Light Dispersion | | :--- | :--- | :--- | | **QTLP673C-R** | **Water Clear** | Focused, high intensity | | **QTLP673C-T** | Diffused | Wider spread, softer glow |