The **LED34H-R** typically refers to a high-performance **Infrared (IR) Emitting Diode**. These components are widely used in industrial sensing, optical encoders, and communication links. Below is a detailed breakdown of its electronic characteristics and specifications. --- ### 1. Technical Specifications The LED34H-R is designed for efficiency in the infrared spectrum. Most variants operate within the following parameters: | Parameter | Typical Value | | :--- | :--- | | **Peak Wavelength** | 880 nm - 940 nm (Infrared) | | **Forward Current ($I_F$)** | 50 mA - 100 mA | | **Forward Voltage ($V_F$)** | 1.3V - 1.7V | | **Reverse Voltage ($V_R$)** | 5.0 V | | **Radiant Intensity** | 10 - 20 mW/sr | | **Viewing Angle** | 20° to 40° (Narrow beam) | | **Operating Temperature** | -40°C to +85°C | --- ### 2. Key Internal Components The electronic functionality of the LED34H-R relies on three main physical parts: * **Semiconductor Die:** Usually made of **Gallium Aluminum Arsenide (GaAlAs)**. This material is chosen for IR LEDs because it allows for high radiant power and high-speed switching. * **The Lead Frame:** Consists of the Anode (+) and Cathode (-) pins. In most radial packages, the longer lead is the Anode. * **Encapsulation (Lens):** A clear or slightly tinted plastic resin that acts as a lens to focus the IR light into a narrow beam, increasing the effective range. --- ### 3. Circuit Integration To use the LED34H-R in a circuit, a current-limiting resistor is mandatory to prevent thermal runaway. #### Standard Wiring Diagram ```text [VCC] --- [Resistor] --- [Anode (LED) Cathode] --- [GND] ``` #### Calculating the Resistor ($R$) Use Ohm's Law: $R = \frac{V_{source} - V_F}{I_F}$ * If $V_{source} = 5V$, $V_F = 1.5V$, and $I_F = 20mA$ (0.02A): * $R = \frac{5 - 1.5}{0.02} = 175 \Omega$ (Use a **180 $\Omega$** standard resistor). --- ### 4. Common Applications * **Optical Encoders:** Used to detect the speed and position of motors. * **Remote Controls:** Transmitting data via IR pulses. * **Smoke Detectors:** Working in tandem with a phototransistor to detect obscuration. * **Safety Light Curtains:** Detecting if an object breaks an invisible light beam in industrial machinery. ---