The **5BC-R/Y** is a specific type of **Bicolor Light Emitting Diode (LED)**. The part number typically describes its physical size, electrical characteristics, and the colors it emits. --- ## 1. Technical Specifications The "5BC" designation usually refers to a **5mm (T-1 3/4) Round Bicolor LED**. This is the standard size for through-hole electronic components. | Feature | Specification | | :--- | :--- | | **Diameter** | 5mm (T-1 3/4) | | **Colors** | Red (R) / Yellow (Y) | | **Type** | Bicolor (Typically 3-lead Common Cathode or 2-lead Bi-polar) | | **Red Wavelength** | ~625 nm - 660 nm | | **Yellow Wavelength** | ~585 nm - 595 nm | | **Forward Voltage (Vf)** | Red: 1.8V - 2.2V / Yellow: 2.0V - 2.4V | | **Operating Current** | 20mA (Standard) | --- ## 2. Terminal Configurations Depending on the specific manufacturer, the 5BC-R/Y generally comes in two pin configurations: ### A. 3-Lead (Common Cathode/Anode) The most common version has three legs. * **Center Pin:** Usually the Common Cathode (Ground). * **Side Pin 1:** Anode for Red. * **Side Pin 2:** Anode for Yellow. * *Mixing:* If both side pins receive power, the LED will glow **Orange**. ### B. 2-Lead (Bi-polar) The colors are wired in anti-parallel. * **Direction A:** Current flows one way to light Red. * **Direction B:** Current is reversed to light Yellow. --- ## 3. Circuit Implementation When connecting this LED to a microcontroller (like an Arduino) or a DC power source, you must use a **Current Limiting Resistor**. ```cpp // Example: Arduino Logic for 3-pin Bicolor LED void setup() { pinMode(9, OUTPUT); // Red Pin pinMode(10, OUTPUT); // Yellow Pin } void loop() { digitalWrite(9, HIGH); // Red ON delay(1000); digitalWrite(9, LOW); digitalWrite(10, HIGH); // Yellow ON delay(1000); } ``` --- ## 4. Common Applications * **Status Indicators:** Red for "Error/Stop" and Yellow for "Standby/Warning." * **Battery Chargers:** Red for "Charging" and Yellow for "Fully Charged." * **Network Equipment:** Indicating different speeds or data activity types.