Arduino PWM Tutorial: Basics, Applications & Techniques

Table of Contents

Understanding PWMPractical Examples: Controlling LED BrightnessLearn to adjust LED brightness using Arduino PWM techniques. This practical guide covers hardware setup, code examples, and troubleshooting tips.
Arduino's PWM CapabilitiesWhat is Arduino? A Beginner's GuideDiscover our in-depth Arduino tutorial covering its history, board architecture, software principles, and practical pro tips.
Core Implementation: analogWrite()
Practical Applications
- LEDYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily. Intensity Control
- Motor Speed RegulationUsing PWM for Precise Speed RegulationMaster PWM for precise motor speed control in Arduino projects. Our detailed guide covers fundamentals, practical examples, and troubleshooting tips.
Advanced Techniques
- FrequencyWhat is PWM?Explore the fundamentals of PWM in Arduino. Discover essential theory, practical tips, and real-world applications to enhance your projects. Customization
- H-BridgeControlling a DC Motor with a Transistor and ArduinoLearn how to safely control DC motors with Arduino using transistor circuits, code examples, and practical wiring diagrams for your robotics projects. Motor Control
TroubleshootingYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily. Guide
Conclusion

Understanding PWM🔗

Pulse Width ModulationPractical Examples: Controlling LED BrightnessLearn to adjust LED brightness using Arduino PWM techniques. This practical guide covers hardware setup, code examples, and troubleshooting tips. (PWM) simulates analog voltage levels using rapid digital switching. The duty cycleWhat is PWM?Explore the fundamentals of PWM in Arduino. Discover essential theory, practical tips, and real-world applications to enhance your projects. (percentage of HIGH time per cycle) determines effective voltage outputUnderstanding Digital Signals and PinsExplore our complete Arduino guide on digital signals and pins, featuring hands-on examples and expert tips for reliable projects.:

Effective Voltage = (Duty Cycle / 255) × 5V  // For 8-bit Arduino

This energy-efficient method is ideal for controlling LEDsYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily., motors, and other analog-like behaviors.

Arduino's PWM Capabilities🔗

PWMPractical Examples: Controlling LED BrightnessLearn to adjust LED brightness using Arduino PWM techniques. This practical guide covers hardware setup, code examples, and troubleshooting tips. availability varies by board:

Board	PWM Pins	Base Frequency	Resolution
Uno/Nano	3,5,6,9,10,11	490Hz/976Hz	8-bit
Mega	2-13, 44-46	490Hz	8-bit
ESP32	All digital pins	1kHz-40MHz	16-bit

PinsDigital Pins and LogicExplore our comprehensive Arduino guide on digital pins and logic. Learn configuration, wiring, troubleshooting, and practical applications. 5 & 6 on Uno/Nano run at 976Hz. Use these for motor control to reduce audible noise.

Core Implementation: analogWrite()🔗

ArduinoWhat is Arduino? A Comprehensive OverviewDive into the world of Arduino with our in-depth guide covering hardware, software, and community projects ideal for students, hobbyists, and educators. abstracts PWM complexity with:

analogWrite(pin, value);  // Value: 0-255

Key Insight: This works only on PWM-capable pinsDigital Pins and LogicExplore our comprehensive Arduino guide on digital pins and logic. Learn configuration, wiring, troubleshooting, and practical applications. (marked with ~ on Uno/Nano).

Practical Applications🔗

LED Intensity Control

CircuitYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily.:

Breathing LED CodeYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily.:

const byte ledPin = 9;
void setup() {
  pinMode(ledPin, OUTPUT);
}
void loop() {
  // Fade in (0 → 255)
  for(int i=0; i<=255; i++) {
    analogWrite(ledPin, i);
    delay(10);
  }
  // Fade out (255 → 0)
  for(int i=255; i>=0; i--) {
    analogWrite(ledPin, i);
    delay(10);
  }
}

Motor Speed Regulation

Essential Components:

void setup() {
  pinMode(5, OUTPUT);  // 976Hz pin
}
void loop() {
  analogWrite(5, 77);  // 30% speed (77/255 ≈ 1.5V)
  delay(3000);
  analogWrite(5, 255); // Full speed
  delay(3000);
}

Advanced Techniques🔗

Frequency Customization

Modify PWM frequencyWhat is PWM?Explore the fundamentals of PWM in Arduino. Discover essential theory, practical tips, and real-world applications to enhance your projects. using timer registers (Uno example):

// Set Timer1 (pins 9,10) to 31.25kHz
void setup() {
  TCCR1B = (TCCR1B & 0b11111000) | 0x01;
  pinMode(9, OUTPUT);
}
void loop() {
  analogWrite(9, 128);  // 50% duty cycle
}

Applications:

31kHz+ for LEDYour First Hands-On Arduino ProjectEmbark on your Arduino journey with our step-by-step guide. Learn to build a simple circuit, write your first code, and troubleshoot your project easily. video recording
20-25kHz for silent motor operation

H-Bridge Motor Control

Combine PWMPractical Examples: Controlling LED BrightnessLearn to adjust LED brightness using Arduino PWM techniques. This practical guide covers hardware setup, code examples, and troubleshooting tips. with direction control:

const byte pwmPin = 5;
const byte in1 = 7, in2 = 8;
void setup() {
  pinMode(pwmPin, OUTPUT);
  pinMode(in1, OUTPUT);
  pinMode(in2, OUTPUT);
}
void loop() {
  // Forward at 70% speed
  digitalWrite(in1, HIGH);
  digitalWrite(in2, LOW);
  analogWrite(pwmPin, 178);  // 178 ≈ 70%
  delay(2000);
  // Reverse at 40% speed
  digitalWrite(in1, LOW);
  digitalWrite(in2, HIGH);
  analogWrite(pwmPin, 102);  // 102 ≈ 40%
  delay(2000);
}

Troubleshooting Guide🔗

Symptom	Likely Cause	Solution
No response	Wrong pin	Use PWM-capable pins
Flickering at low duty	Low frequency	Increase PWM frequency
Motor vibration	Insufficient duty cycle	Maintain >20% duty cycle
Timer conflicts	Shared timer resources	Reassign pins
Electrical noise	High-frequency interference	Add RC filter to circuit