Buzzer / Piezo
Controlling Active Buzzer Buzzer / Piezo with Arduino Uno
What is the Active Buzzer?
A buzzer with a built-in oscillator — just apply power to get a fixed-tone beep, no PWM signal generation required.
Specifications
| Operating voltage | 3V - 5V DC (5V typical on breakout modules) |
| Current draw | ~25-30 mA |
| Tone | Fixed frequency, ~2-4kHz — set by the buzzer's internal oscillator, not by your code |
| Control | Digital HIGH/LOW only — a plain digitalWrite() is enough, no tone() or PWM needed |
Active Buzzer Pinout
| Pin | Name | Description |
|---|---|---|
| 1 | VCC | Power, 3V-5V DC |
| 2 | GND | Ground |
| 3 | I/O | Signal input — HIGH turns the tone on, LOW turns it off |
Easy to tell apart from a passive buzzer without a multimeter: tap 5V straight to the pin briefly — an active buzzer beeps immediately, a passive one just clicks.
Setting Up Active Buzzer with Arduino Uno
Wiring
| Component pin | Arduino Uno pin | Note |
|---|---|---|
| VCC | 5V | — |
| GND | GND | — |
| I/O | D8 | Any digital pin works — this is a plain HIGH/LOW signal, not PWM |
Example code
This is an active buzzer (built-in oscillator) — do not use tone(), which is for passive buzzers that need a driven frequency. A plain digitalWrite HIGH/LOW is all it needs, and driving it with tone() will not change the pitch.
Related Guides & Projects
Arduino Uno R3 Pinout: Every Pin Explained (Digital, Analog, PWM, Power)
Complete Arduino Uno R3 pinout reference: all 14 digital pins, 6 analog inputs, PWM, UART, SPI, I2C, AREF, and power rails explained with wiring tips and common mistakes.
Ultimate Arduino Mega 2560 Pinout Guide: Complete Power & I/O Reference
Master the Arduino Mega 2560 pinout. Detailed reference for all 54 digital pins, 16 analog inputs, PWM, UARTs, SPI, I2C, interrupts, and power. Includes a printable table and practical wiring tips.
Interfacing HC-SR04 Ultrasonic Sensor with Arduino
Measure distance accurately using ultrasonic sound waves and an Arduino Uno — no complex math, no expensive hardware.
HC‑SR04 Ultrasound Distance Measurement with Arduino – Parking Alert (LCD & Buzzer)
Learn HC‑SR04 ultrasound distance measurement with Arduino Uno. Build a parking alert system with 16x2 LCD and buzzer – shows distance and beeps faster as you approach.