It appears you are referring to the **LED89**, which is a specific designation often used for **IR (Infrared) Emitting Diodes** or specific display modules. Most commonly, this refers to high-intensity infrared LEDs used in remote controls, optical sensors, and smoke detectors. --- ### 1. Key Technical Specifications Below are the typical electronic characteristics of a standard LED89 infrared component: | Parameter | Typical Value | Unit | | :--- | :--- | :--- | | **Peak Wavelength** | 940 | nm (Nanometers) | | **Forward Current ($I_F$)** | 50 - 100 | mA | | **Forward Voltage ($V_F$)** | 1.2 - 1.5 | Volts | | **Radiant Intensity** | 20 - 50 | mW/sr | | **Viewing Angle** | 20 - 40 | Degrees | --- ### 2. Internal Electronic Structure The LED89 is a semiconductor p-n junction diode. Its operation is defined by several core parts: * **Die (Chip):** Usually made of **Gallium Arsenide (GaAs)** or Aluminum Gallium Arsenide (AlGaAs). This material determines the 940nm infrared light frequency. * **Anode (+):** The longer lead or the internal part connected to the smaller electrode. * **Cathode (-):** The shorter lead, usually identified by a flat edge on the plastic encapsulation. * **Epoxy Lens:** A clear or blue-tinted plastic housing that focuses the infrared beam. --- ### 3. Basic Circuit Diagram To use an LED89, you must use a current-limiting resistor to prevent the component from burning out. ```text VCC (5V) ---- [ Resistor ] ---- (Anode) LED89 (Cathode) ---- GND ``` **Calculating the Resistor ($R$):** Using Ohm's Law: $R = (V_{source} - V_F) / I_F$ * *Example:* For a 5V supply, 1.3V drop, and 20mA current: * $R = (5 - 1.3) / 0.020 = 185 \Omega$ (Use a standard $220 \Omega$ resistor). --- ### 4. Common Applications The LED89 series is widely utilized in the following electronic systems: 1. **Remote Controls:** Sending modulated signals to TVs and Air Conditioners. 2. **Optical Switches:** Used in "break-beam" sensors to detect objects passing between an IR LED and a phototransistor. 3. **Encoders:** Used in computer mice or industrial motors to count rotations. 4. **Security Systems:** Light source for night-vision cameras (active IR illumination).