Active buzzer module (high-level trigger)
Active buzzer module pinout (I/O, VCC, GND), high- vs low-level trigger types, and why a module with a transistor is safer than a bare buzzer on a GPIO.
Community draft — report a mistake
3.3 V or 5 V? The I/O pin only drives the module's transistor, so a 3.3 V GPIO is enough even when the buzzer runs from 5 V. Check the label: "high-level trigger" beeps when I/O is HIGH; "low-level trigger" modules (with a PNP transistor) beep when I/O is LOW.
An active buzzer has its own oscillator inside: give it DC and it beeps at a fixed pitch. The 3-pin module adds a small transistor and a resistor, so the board’s GPIO only supplies a few milliamps instead of the 25–30 mA the buzzer draws.
That transistor is the reason to buy the module rather than a bare buzzer: a bare 5 V buzzer straight on a GPIO pulls more current than an ESP32 or Pico pin is rated for.
Pin order varies between makers — some print S / + / −, others I/O / VCC / GND. Wire by the printed labels, not by position.
Pinout
| Pin | What it does |
|---|---|
I/O | Signal from the board — HIGH = beep on high-level-trigger modules |
VCC | 3.3–5 V supply for the buzzer |
GND | Ground, shared with the board |
Use it with
- Active buzzer module (high-level trigger) with Arduino Nano Arduino C++
- Active buzzer module (high-level trigger) with Arduino Uno R3 Arduino C++
- Active buzzer module (high-level trigger) with ESP32 DevKit V1 Arduino C++
- Active buzzer module (high-level trigger) with NodeMCU ESP8266 Arduino C++
- Active buzzer module (high-level trigger) with Raspberry Pi Pico W MicroPython
Common errors
Buzzer beeps all the time and stops when the pin goes HIGH
You have a low-level-trigger module. Invert the logic in code (LOW = on) or buy the high-level type.
Only a click, no tone
That is a passive buzzer, which needs a square wave (tone()) instead of a steady HIGH. Active buzzers have a sealed back and beep on plain DC.
Quiet at 3.3 V
Most 5 V active buzzers are softer at 3.3 V. Power VCC from 5 V — the I/O pin can still come from a 3.3 V board because it only drives the transistor.