06
intermediate+300 XP

Potentiometer LED Dimmer

Use a potentiometer to smoothly control LED brightness through PWM.

🎯 Objective

Read a potentiometer with analogRead() and use analogWrite() to dim an LED.

📖 Background Theory

**Analog input:** analogRead(A0) returns 0–1023 based on voltage at the pin (0V = 0, 5V = 1023). **PWM output:** analogWrite(pin, 0-255) generates a PWM signal. - duty cycle = value/255 - 0 = fully OFF, 255 = fully ON, 128 = 50% brightness **Mapping values:** Arduino's map() function remaps a range: map(value, 0, 1023, 0, 255) scales 0-1023 to 0-255 This is how real dimmer switches work — using PWM to reduce average power!

🔧 Components You'll Use

Arduino UnoPotentiometerLedResistorGround

📋 Steps (6)

  1. 1Place Arduino Uno, Potentiometer, LED, Resistor, Battery, and Ground
  2. 2Wire Potentiometer VCC to 5V, GND to Ground
  3. 3Wire Potentiometer wiper (SIG) to Arduino A0
  4. 4Wire Arduino D9 (PWM~) → 220Ω resistor → LED → Ground
  5. 5Paste the starter code and run simulation
  6. 6Turn the potentiometer knob to control brightness!