BinKey

5mm-led-red

3 min read

Important Note

This entire repo was AI created - including all of the data within. The intent was to A) help me with my personal electronics inventory; and B) see how I could use AI to make that process a bit easier. DO NOT TRUST!

5mm LED Red

Details

  • Location: Cabinet-1, Bin 9
  • Category: LEDs
  • Color: Red
  • Size: 5mm

Description

Standard 5mm red LED for general purpose lighting and indicators.

Image

5mm LED Red

Specifications

  • Forward Voltage: 1.8V - 2.2V (typical 2.0V)
  • Forward Current: 20mA (maximum)
  • Luminous Intensity: 20-50 mcd (typical)
  • Viewing Angle: 30° - 60°
  • Wavelength: 620-630nm (red)
  • Package: 5mm through-hole
  • Lens: Clear or diffused

Wiring Examples

Basic LED Circuit (Arduino/5V)

Arduino 5V → 220Ω Resistor → LED Anode (long leg)
LED Cathode (short leg) → Arduino GND

Resistor calculation: R = (5V - 2V) / 0.02A = 150Ω
Use 220Ω for safety margin

Basic LED Circuit (3.3V Systems)

3.3V → 100Ω Resistor → LED Anode (long leg)
LED Cathode (short leg) → GND

Resistor calculation: R = (3.3V - 2V) / 0.02A = 65Ω
Use 100Ω for safety margin

Digital Control Circuit

Arduino Pin 13 → 220Ω Resistor → LED Anode
LED Cathode → Arduino GND

Code: digitalWrite(13, HIGH) turns LED on

PWM Brightness Control

Arduino PWM Pin (3,5,6,9,10,11) → 220Ω Resistor → LED Anode
LED Cathode → Arduino GND

Code: analogWrite(pin, 0-255) controls brightness

LED Identification

Physical Identification

  • Anode (Positive): Longer leg, larger internal element
  • Cathode (Negative): Shorter leg, flat side of LED body
  • Polarity: LEDs only work in one direction

Testing

  • Use multimeter diode test function
  • Apply 3V with 1kΩ resistor to test
  • LED should light when connected correctly

Current Limiting

Why Resistors Are Required

  • LEDs have very low internal resistance
  • Without current limiting, LED will draw excessive current
  • Excessive current causes overheating and LED failure
  • Always use appropriate current limiting resistor

Resistor Value Calculation

R = (Supply Voltage - LED Forward Voltage) / Desired Current

For 5V supply with red LED:
R = (5V - 2V) / 0.02A = 150Ω (use 220Ω for safety)

For 3.3V supply with red LED:
R = (3.3V - 2V) / 0.02A = 65Ω (use 100Ω for safety)

Programming Examples

void setup() {
  pinMode(13, OUTPUT);
}
 
void loop() {
  digitalWrite(13, HIGH);  // Turn LED on
  delay(1000);             // Wait 1 second
  digitalWrite(13, LOW);   // Turn LED off
  delay(1000);             // Wait 1 second
}

Arduino Fade Code

int ledPin = 9;    // PWM pin
 
void setup() {
  // No setup needed for PWM
}
 
void loop() {
  // Fade in
  for (int brightness = 0; brightness <= 255; brightness++) {
    analogWrite(ledPin, brightness);
    delay(5);
  }
 
  // Fade out
  for (int brightness = 255; brightness >= 0; brightness--) {
    analogWrite(ledPin, brightness);
    delay(5);
  }
}

Applications

  • Status indicators
  • Power-on indicators
  • Error/warning lights
  • Decorative lighting
  • Prototyping and testing
  • Educational projects
  • Simple displays

Safety Notes

  • Never connect LED directly to power without current limiting
  • Check polarity before connecting
  • Use appropriate resistor values
  • Avoid exceeding maximum current rating
  • Handle with care to avoid damage to leads

Tags

led red 5mm standard

Graph View

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