The **ALTG-111-R** is a specific electronic component, typically categorized as a **Surface Mount Device (SMD) LED indicator** or a specialized signal lamp used in industrial and consumer electronics. Below is a detailed breakdown of its electronic characteristics and specifications. --- ### 1. General Specifications The ALTG-111-R is primarily defined by its optical output and physical footprint. | Feature | Specification | | :--- | :--- | | **Component Type** | Light Emitting Diode (LED) | | **Color** | Red | | **Mounting Type** | Surface Mount (SMD/SMT) | | **Package/Case** | Standard industry footprint (often 0603 or 0805 depending on manufacturer) | | **RoHS Status** | Compliant (Lead-free) | --- ### 2. Electrical Characteristics To ensure the longevity of the component, it must be operated within specific electrical parameters. * **Forward Voltage ($V_f$):** Typically ranges from **1.8V to 2.2V**. This is the voltage required to "turn on" the diode. * **Forward Current ($I_f$):** Standard operating current is usually **20mA**. Running above this without a current-limiting resistor will cause thermal failure. * **Peak Forward Current:** Can handle brief pulses up to **100mA** (at 1/10 duty cycle). * **Reverse Voltage ($V_r$):** Usually rated for a maximum of **5V**. --- ### 3. Optical Properties The "R" in the part number signifies the Red spectrum. * **Dominant Wavelength:** Approximately **625nm to 640nm** (Standard Red). * **Luminous Intensity:** Measured in millicandela (mcd), typically ranging from **20mcd to 80mcd** depending on the lens transparency. * **Viewing Angle:** Often **120° to 140°**, providing wide visibility for status indication. --- ### 4. Implementation Details When integrating the ALTG-111-R into a circuit, engineers must consider the following: #### Circuit Schematic (Example) ```cpp // Basic Current Limiting Calculation // R = (V_source - V_forward) / I_forward // If V_source = 5V and I_forward = 0.02A: // R = (5V - 2.0V) / 0.02A = 150 Ohms ``` #### Key Considerations 1. **Polarity:** Being a diode, it is polarized. The cathode is usually marked with a green stripe or a notch on the underside of the SMD package. 2. **Soldering:** Should be soldered using Reflow Soldering profiles to avoid "popcorning" (moisture expansion) within the epoxy. 3. **Heat Dissipation:** While low power, dense arrays of these LEDs require adequate copper pour on the PCB to act as a heat sink. ---