ESP32 - Potentiometer Triggers Piezo Buzzer
This tutorial instructs you how to use ESP32 and the potentiometer to control the piezo buzzer. In detail:
- The ESP32 automatically turns the piezo buzzer on if the potentiometer's analog value is above a threshold
- The ESP32 automatically turns the piezo buzzer off if the potentiometer's analog value is under a threshold
We also learn how to convert the analog value to voltage and then use the voltage threshold to control the piezo buzzer:
- The ESP32 automatically turns the piezo buzzer on if the potentiometer's voltage is above a threshold.
- The ESP32 automatically turns the piezo buzzer off if the potentiometer's voltage is under a threshold.
We will use piezo buzzer to make sound and melody of song.
Hardware Used In This Tutorial
1 | × | ESP-WROOM-32 Dev Module | |
1 | × | Micro USB Cable | |
1 | × | Potentiometer | |
1 | × | Piezo Buzzer | |
1 | × | Breadboard | |
1 | × | Jumper Wires | |
1 | × | (Optional) DC Power Jack | |
1 | × | (Optional) ESP32 Screw Terminal Adapter |
Or you can buy the following sensor kit:
1 | × | DIYables Sensor Kit 30 types, 69 units |
Introduction to Piezo Buzzer and Potentiometer
We have specific tutorials about piezo buzzer and potentiometer. Each tutorial contains detailed information and step-by-step instructions about hardware pinout, working principle, wiring connection to ESP32, ESP32 code... Learn more about them at the following links:
Please note that this tutorial use 3-5V buzzer, but you can adapt it for 12v buzzer. you can learn about ESP32 - Buzzer tutorial
Wiring Diagram

This image is created using Fritzing. Click to enlarge image
ESP32 Code - Simple Sound - Analog Threshold
Quick Instructions
- If this is the first time you use ESP32, see how to setup environment for ESP32 on Arduino IDE.
- Do the wiring as above image.
- Connect the ESP32 board to your PC via a micro USB cable
- Open Arduino IDE on your PC.
- Select the right ESP32 board (e.g. ESP32 Dev Module) and COM port.
- Copy the above code and paste it to Arduino IDE.
- Compile and upload code to ESP32 board by clicking Upload button on Arduino IDE
- Rotate the potentiometer
- Listen to piezo buzzer's sound
Line-by-line Code Explanation
The above ESP32 code contains line-by-line explanation. Please read the comments in the code!
ESP32 Code - Simple Sound - Voltage Threshold
The analog value read from the potentiometer is converted to voltage, and then the voltage is compared to a voltage threshold. If it exceeds the threshold, it triggers Piezo Buzzer
ESP32 Code - Melody - Voltage Threshold
Quick Instructions
- If this is the first time you use ESP32, see how to setup environment for ESP32 on Arduino IDE.
- Copy the above code and paste it to Arduino IDE.
- Create the pitches.h file On Arduino IDE:

- Either click on the button just below the serial monitor icon and choose "New Tab", or use Ctrl+Shift+N.
- Give file's name pitches.h and click OK button
- Copy the below code and paste it to that file.
- Compile and upload code to ESP32 board by clicking Upload button on Arduino IDE
- Rotate the potentiometer
- Listen to piezo buzzer's melody
Line-by-line Code Explanation
The above ESP32 code contains line-by-line explanation. Please read the comments in the code!
Video Tutorial
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