Arduino Push Button Control LED – Simple Project for Beginners

Introduction

In this project, we will learn how to control an LED using a push button with Arduino. This is one of the most basic and important projects for beginners in electronics and Arduino. By doing this project, students can understand how digital input and digital output work in Arduino.

Components Required

Arduino Uno
Push Button
LED
220 Ω Resistor
10 kΩ Resistor (for button – optional)
Breadboard
Connecting Wires

Circuit & Description

Connect one side of the push button to 5V.
Connect the LED to pin 13, using a resistor 220Ω connect the other LED pin to the ground of Arduino
Connect the other side of the button to pin 2 of Arduino.
Connect a 10 kΩ resistor from pin 2 to GND (pull-down resistor).

This pull-down resistor ensures that the input pin reads LOW when the button is not pressed.

Arduino Program


const int buttonPin = 2;     // push button connected to pin 2
const int ledPin = 13;      // LED connected to pin 13

int buttonState = 0;        // variable to store button state

void setup() {
  pinMode(ledPin, OUTPUT);     // LED as output
  pinMode(buttonPin, INPUT);  // Button as input
}

void loop() {
  buttonState = digitalRead(buttonPin);  // read button

  if (buttonState == HIGH) {
    digitalWrite(ledPin, HIGH);   // LED ON
  } else {
    digitalWrite(ledPin, LOW);    // LED OFF
  }
}

Working Principle

Arduino continuously reads the state of the push button using digitalRead().
When the button is pressed, the input pin becomes HIGH.
Arduino sends HIGH signal to LED pin using digitalWrite().
The LED glows.
When the button is released, the input becomes LOW and the LED turns OFF.

Alternative Method (Using Internal Pull-up Resistor)

We can avoid using an external 10kΩ resistor by using Arduino’s internal pull-up resistor.

Change this line in setup():


pinMode(buttonPin, INPUT_PULLUP);

And modify the logic:


if (buttonState == LOW) {
  digitalWrite(ledPin, HIGH);
} else {
  digitalWrite(ledPin, LOW);
}

Note: Logic is inverted because of pull-up resistor.

Applications

Door bell switch
Keyboard keys
Control systems
Digital input testing
Student practice project

Advantages

Very simple project
Easy to understand
Low cost
Good for beginners

Conclusion

This project helps beginners understand how a push button works with Arduino and how to control an LED using digital input. It is an important base project before learning sensors, relays, and motors.

Basic Electronics for Beginners

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