Tutorial 19 – Using a Potentiometer for Analog Input

Welcome back to CraftedTech Engineering's Arduino tutorial series! In this tutorial, we’ll explore how to use a potentiometer to provide analog input to your Arduino. Potentiometers are great for controlling variables, such as the brightness of an LED or the speed of a motor, making them a fundamental part of many projects.

🔌 What You’ll Need

1 Arduino Board (e.g., Arduino UNO)
1 Potentiometer (10kΩ is typical)
1 LED (any color)
1 220Ω Resistor
Breadboard
Jumper wires
USB cable for Arduino

You can order the required components here:

🧠 What Is a Potentiometer?

A potentiometer is a three-terminal variable resistor that allows you to adjust its resistance by turning a knob or slider. This change in resistance can be read by your Arduino as an analog value (ranging from 0 to 1023), making it useful for controlling analog outputs like LED brightness or motor speed.

🧾 Step-by-Step Instructions

🔧 Step 1: Wiring the Potentiometer and LED

Connect one outer leg of the potentiometer to 5V on the Arduino.
Connect the other outer leg of the potentiometer to GND (ground).
Connect the middle leg (wiper) of the potentiometer to analog pin A0 on the Arduino.
For the LED:

1. Connect the long leg (anode) of the LED to digital pin 9 on the Arduino.
2. Connect the short leg (cathode) of the LED to one end of the 220Ω resistor.
3. Connect the other end of the resistor to GND.

💻 Step 2: Arduino Code to Read Potentiometer and Control LED

int potPin = A0;   // Pin connected to the potentiometer
int ledPin = 9;     // Pin connected to the LED
int potValue = 0;   // Variable to store potentiometer value

void setup() {
  pinMode(ledPin, OUTPUT);    // Set LED pin as output
  Serial.begin(9600);         // Start serial communication
}

void loop() {
  potValue = analogRead(potPin);            // Read potentiometer value
  int ledBrightness = map(potValue, 0, 1023, 0, 255);  // Map potentiometer value to 0-255
  analogWrite(ledPin, ledBrightness);      // Control LED brightness
  Serial.println(potValue);                // Output potentiometer value to Serial Monitor
  delay(10);                              // Small delay for stability
}

🔍 Code Breakdown

analogRead(): Reads the analog value from the potentiometer (from 0 to 1023).
map(): Maps the potentiometer value (0-1023) to a range of 0-255 (for LED brightness control).
analogWrite(): Adjusts the LED brightness based on the mapped potentiometer value.
Serial.println(): Outputs the potentiometer value to the Serial Monitor for debugging.

🧪 Try This!

Change the LED's behavior by controlling its brightness with the potentiometer.
Try using the potentiometer to control other outputs, such as a motor or the speed of a fan.
Experiment with mapping different ranges of the potentiometer value to control various aspects of your project.

🛠️ Troubleshooting Tips

Make sure the potentiometer’s middle leg (wiper) is connected to the correct analog input pin.
If the LED isn't responding, check the wiring of the LED and resistor.
Ensure the potentiometer is working by printing its value to the Serial Monitor.

🧭 What You Learned in This Tutorial

✔️ How to use a potentiometer to provide analog input to Arduino
✔️ How to map analog values for controlling outputs like LED brightness
✔️ How to use analogWrite() for PWM control of outputs
✔️ Basic interaction with analog inputs in Arduino projects

📌 Next Up: Tutorial 20 – Controlling a Servo Motor with Arduino

In the next tutorial, we’ll use the potentiometer to control the position of a servo motor, demonstrating another useful application of analog input in Arduino projects.

📣 Don’t forget to follow CraftedTech Engineering for more hands-on tutorials and project ideas!

🔗 Website: craftedtechengineering.com
📘 Facebook: @CraftedTechEngineering
📺 YouTube: @CraftedTechEngineering

Back to blog

Item added to your cart