Buzzer

A small part that makes sound: active and passive types.

Schematic letter: BZ
Unit / key rating: Voltage (V), frequency (Hz)

Pinout

+ (long lead): Positive; the body is marked +.
−: Negative.

Real photos

What is it for?

An active buzzer has its own oscillator inside: apply voltage and it beeps at one tone. A passive buzzer is like a speaker: feed it a square wave and it sounds at that frequency, so it can play melodies.

Used in alarms, warning beeps and Arduino projects.

Things to watch out for

⚠ Active and passive buzzers look alike: the active one's underside is usually sealed (black resin), the passive one shows a board.
⚠ On an Arduino, tone() only plays different notes on a passive buzzer.

🔒 This content is in the repair pack

The repair pack unlocks all interactive content in one go: diagrams and current flows, the Repair Workshop, simulations, concepts, IC guides, the Component Library and comparison guides. One sample in every section is free.

Repair pack: 5,000 ₺, members get 10% off → 4,500 ₺. Or 1-week access for 1,000 ₺.