20 Pieces Green LED – Super Bright Standard Green LED 5mm

Description

Here is a complete description of the 5 mm colored LEDs (not 5 cm) and a full guide for use with Arduino, including practical programming examples.

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🔌 LED Description (5 mm Light Emitting Diode)

📏 General Characteristics

• Type: LED (Light Emitting Diode)
• Diameter: 5 mm
• Typical Operating Voltage:
  • Red: 1.8–2.2 V
  • Yellow: 2.0–2.2 V
  • Green: 2.0–3.2 V
  • Blue: 3.0–3.4 V
  • White: 3.0–3.4 V
• Recommended Current: 10-20 mA
• Polarity: Anode (positive, longer leg) and Cathode (negative, shorter leg)

🎨 Available Colors

• Green LED: Used to indicate active state or OK.
• Red LED: Signifies warnings, errors, or power.
• White LED: For illumination or neutral signaling.
• Yellow LED: Attention or standby state.
• Blue LED: Modern, often used for power-on or special state.

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🛠️ Guide for use with Arduino

🔧 Required Components

• Arduino UNO (or compatible)
• 220Ω or 330Ω resistors
• 5mm LED (color choice)
• Breadboard
• Jumper wires

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📈 Connection diagram (single LED)

Arduino PIN (es. 13) ---> Resistenza (220Ω) ---> Anodo LED
                                      |
                                  Catodo ---> GND

• Connect the long leg of the LED (anode) through a 220Ω resistor to a digital pin of Arduino.
• Connect the short leg (cathode) to the GND of Arduino.

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💻 Example code: turn on an LED

// Pin a cui è collegato il LED
int ledPin = 13;

void setup() {
  pinMode(ledPin, OUTPUT); // imposta il pin come uscita
}

void loop() {
  digitalWrite(ledPin, HIGH); // accende il LED
  delay(1000);                // attende 1 secondo
  digitalWrite(ledPin, LOW);  // spegne il LED
  delay(1000);                // attende 1 secondo
}

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🧪 Example: turn on 5 LEDs of different colors

⚙️ Connection

LED	Arduino PIN	Resistance
Red	2	220Ω
Green	3	220Ω
Yellow	4	220Ω
Blue	5	330Ω
White	6	330Ω

🔤 Arduino Code for LED Sequence

int ledRosso = 2;
int ledVerde = 3;
int ledGiallo = 4;
int ledBlu = 5;
int ledBianco = 6;

void setup() {
  pinMode(ledRosso, OUTPUT);
  pinMode(ledVerde, OUTPUT);
  pinMode(ledGiallo, OUTPUT);
  pinMode(ledBlu, OUTPUT);
  pinMode(ledBianco, OUTPUT);
}

void loop() {
  digitalWrite(ledRosso, HIGH);
  delay(500);
  digitalWrite(ledRosso, LOW);

  digitalWrite(ledVerde, HIGH);
  delay(500);
  digitalWrite(ledVerde, LOW);

  digitalWrite(ledGiallo, HIGH);
  delay(500);
  digitalWrite(ledGiallo, LOW);

  digitalWrite(ledBlu, HIGH);
  delay(500);
  digitalWrite(ledBlu, LOW);

  digitalWrite(ledBianco, HIGH);
  delay(500);
  digitalWrite(ledBianco, LOW);
}

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📘 Practical Tips

• Use different resistances for each color to avoid damage: blue and white require higher values.
• If you want more control, consider using transistor o LED driver for higher current.
• You can combine these LEDs to create a traffic light, a status indicator, or simple light effects.

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🧠 Advanced Experiments

• PWM (Pulse Width Modulation): Use analogWrite(pin, valore) to adjust brightness.
• Sensors: Turn on LEDs in response to light, temperature, or motion sensors.
• Light effects: Create breathing, random flashing, or music-synced effects.

 

Great! Here are 3 advanced examples of using 5mm LEDs with Arduino:

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🚦 1. Street traffic light with LEDs

🔧 Components

• 1 Red LED (Pin 2)
• 1 Yellow LED (Pin 3)
• 1 Green LED (Pin 4)
• 3 Resistors (220Ω)
• Arduino, breadboard, jumper

💡 Diagram

Connect the LEDs through resistors to pins 2, 3, 4 respectively and GND.

🧠 Code

int ledRosso = 2;
int ledGiallo = 3;
int ledVerde = 4;

void setup() {
  pinMode(ledRosso, OUTPUT);
  pinMode(ledGiallo, OUTPUT);
  pinMode(ledVerde, OUTPUT);
}

void loop() {
  digitalWrite(ledRosso, HIGH);
  delay(3000); // 3 secondi
  digitalWrite(ledRosso, LOW);
  
  digitalWrite(ledGiallo, HIGH);
  delay(1000); // 1 secondo
  digitalWrite(ledGiallo, LOW);

  digitalWrite(ledVerde, HIGH);
  delay(3000); // 3 secondi
  digitalWrite(ledVerde, LOW);
}

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🔘 2. LED Toggle with Button (on/off switch)

🔧 Components

• 1 LED (e.g., Blue, Pin 8)
• 1 LED Resistor (330Ω)
• 1 Button (Pin 7)
• 1 Pull-down Resistor (10kΩ)
• Arduino

🔌 Connection

• LED (Anode to Pin 8 through resistor, Cathode to GND)
• Button between Pin 7 and 5V, with pull-down between Pin 7 and GND

🧠 Code

int ledPin = 8;
int buttonPin = 7;
bool statoLED = false;
bool statoPrecedente = false;

void setup() {
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop() {
  bool lettura = digitalRead(buttonPin);
  if (lettura == HIGH && statoPrecedente == LOW) {
    statoLED = !statoLED;
    digitalWrite(ledPin, statoLED);
    delay(200); // debounce
  }
  statoPrecedente = lettura;
}

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📱 3. Control LED via Bluetooth (from App)

🔧 Components

• LED (Red – Pin 10)
• HC-05 Bluetooth module (TX/RX)
• Arduino UNO

📲 Recommended App: Serial Bluetooth Terminal (Android) or similar

🧠 Connection

• Red LED at Pin 10 (through 220Ω resistor)
• HC-05:
  • TX ➝ RX (Pin 0 of Arduino)
  • RX ➝ TX (Pin 1 of Arduino, with voltage divider)
  • VCC ➝ 5V
  • GND ➝ GND

🔥 Note: disconnect TX/RX when uploading the sketch to Arduino.

🧠 Code

int ledPin = 10;
char comando;

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  if (Serial.available()) {
    comando = Serial.read();
    if (comando == '1') {
      digitalWrite(ledPin, HIGH);
    } else if (comando == '0') {
      digitalWrite(ledPin, LOW);
    }
  }
}

📲 Commands from the app

• Send 1 ➝ LED on
• Send 0 ➝ LED off

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Perfect! The effect “breathing” (also known as fading LED) simulates the behavior of a light that slowly turns on and off, just like if it were “breathing”. It’s a great exercise to learn about PWM (Pulse Width Modulation) with Arduino.

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🌬️ Project: LED with breathing effect (fading)

🔧 Required Components

• 1 LED (preferably White, Blue or Green for a nice visual effect)
• 1 Resistor 220–330Ω
• Arduino UNO
• Breadboard and jumper

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🔌 Connection diagram

Component	Connection
LED anode	Pin 9 (PWM)
LED cathode	GND (via 220Ω resistor)

The Pin 9 of Arduino supports PWM (you can see it with the symbol ~).

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💻 Arduino code: breathing effect

int ledPin = 9;       // Pin PWM
int luminosita = 0;   // Valore PWM (0-255)
int variazione = 5;   // Incremento/decremento luminosità

void setup() {
  pinMode(ledPin, OUTPUT);
}

void loop() {
  analogWrite(ledPin, luminosita); // imposta la luminosità

  luminosita += variazione;        // cambia luminosità

  // Inverti direzione al raggiungimento di estremi
  if (luminosita <= 0 || luminosita >= 255) {
    variazione = -variazione;
  }

  delay(30); // tempo tra i cambi (più alto = respiro più lento)
}

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🧪 Additional experiments

• Modify delay(30) to make the breathing effect slower or faster.
• Change variazione a 1 for a softer effect.
• Try with a RGB LED to fade through multiple colors (want an RGB example? I can give it to you!)

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🎨 Variant: “sinusoidal breathing” (more natural)

For a more realistic effect, you can use the sine function to model the brightness (requires the library math.h on some Arduino versions):

int ledPin = 9;
float x = 0;

void setup() {
  pinMode(ledPin, OUTPUT);
}

void loop() {
  float valore = (sin(x) + 1.0) * 127.5; // da 0 a 255
  analogWrite(ledPin, int(valore));
  x += 0.05;
  if (x > TWO_PI) x = 0;
  delay(20);
}

This creates a softer “breathing” effect, similar to that of Apple devices or smart devices.

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Tutorial: How to use LED GREEN – Standard super bright green LED diode from 5 mm

These green LEDs are ideal for anyone starting with Arduino and wanting to add a bit of light to their projects. They are useful for signaling states, creating indicators, or simply illuminating the environment.

What you need

• Arduino Uno
• Jumper cable
• Breadboard

Steps

1. Check the datasheet for the operating voltage and maximum current of the green LED. Generally, for a standard 5mm green LED, a resistor is used between the Arduino digital pin and the anode (cathode) of the LED.
2. Connect the cathode (short pin on the LED housing) to the GND of the Arduino through a jumper wire.
3. Connect the anode (long pin on the LED housing) to a resistor. Check the datasheet for the maximum current to choose the right resistor, generally between 220 and 330 ohms.
4. Connect the end of the resistor not connected to GND to a digital pin on the Arduino (example: pin 13).
5. Open Arduino IDE and upload the following sketch to your Arduino.
6. Verify the correct illumination of the LED when the digital pin is activated. If the LED does not light up, reverse the polarity or check the resistors.
7. If necessary, modify the sketch to test other digital pins and vary the illumination.
8. Explore further projects such as creating an led timer or a lighting sequence.

Example code

void setup() {
  pinMode(13, OUTPUT);
}

void loop() {
  digitalWrite(13, HIGH); // Accende il LED verde collegato al pin 13
  delay(500);
  digitalWrite(13, LOW); // Spegne il LED
  delay(500);
}

Mini project

Create an led timer that automatically turns on and off your green led every minute. Use a button to start or stop the timer.

Common mistakes

• Reverse connection of the led
• Too low or too high resistance
• Digital pin not properly configured as output.
• Modifying the sketch without testing the resistances and connections.

Recommended accessories

• Arduino Uno R3
• Rgb jumper cable
• Arduino prototyping board

Frequently asked questions

How can I control multiple leds from a single pin?
Use a multiplexer or a transistor as a switch to control multiple leds with a single pin.

What is the difference between a green led and a red one?
The main difference lies in the wavelength of the emitted light, which determines the color. Green leds have a different wavelength than red leds.

Can I use these leds without Arduino?
Yes, you can directly connect LEDs to batteries or other circuits for simple illumination.