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Passive Buzzer (Piezo)

Sound

Piezo buzzer without its own oscillator. Plays any frequency through Arduino's tone() function; used for alarms, warning sounds and simple melodies.

Specifications

Type

Passive (no oscillator) piezo

Operating voltage

3 - 5V

Driving

Square wave with tone()

Legs

+ (long / red), – (short / black)

Shop prices

• RobotistanIn stock6.55 ₺
• Robo90In stock9.52 ₺
• MotorobitIn stock10.10 ₺
• HobiDevreIn stock10.56 ₺
• SAMM MarketIn stock11.91 ₺
• KomponentciIn stock14.34 ₺
• RobocomboIn stock16.50 ₺
• RobotzadeOut of stock8.40 ₺

Prices read from the shops' pages on 22 October 2026. Prices and stock may have changed since; check at the shop before you buy.

Projects with this part

• Doorbell with a BuzzerBeginner20 minA doorbell that plays a four-note "ding-dong" on a passive buzzer when you press the button; every ring is also written to the Serial Monitor. It teaches making sound with tone(), keeping notes and their lengths in arrays and playing them with a for loop, gathering a job into its own function, and reading a button with the Arduino's built-in pull-up resistor (INPUT_PULLUP). You can make the tune your own by changing the notes in the code. No extra library needed.Open project
• Parking SensorIntermediate45 minLike the parking sensor in a car: the HC-SR04 measures the distance to whatever is in front of it, the buzzer starts beeping once something comes within 1 metre and the beeps get faster as it comes closer; below 10 cm the tone is steady. Green, yellow and red LEDs show the far, middle and near zones, and the distance is written to the Serial Monitor. It teaches timing with millis() instead of delay, so measuring, beeping and the lights run without waiting for each other, writing a function that returns a value, splitting into zones with if / else if, and turning the distance into a beep gap with map. No extra library needed.Open project
• Motion AlarmBeginner25 minA small home alarm that goes off when someone walks in: the HC-SR501 PIR sensor senses the change in the heat a human body gives off, the buzzer plays a two-tone siren and the red LED blinks; every alarm is counted in the Serial Monitor. It teaches reading a sensor's digital output, catching only the moment motion starts, sounding for a set time with millis(), and gathering the job into its own function. No extra library needed.Open project
• Smoke and Gas AlarmIntermediate35 minAn alarm that goes off when smoke or a flammable gas (LPG, natural gas, methane) shows up in the kitchen or a room: the MQ-2 sensor's analog output is read, the clean air value is measured at start-up, and once the reading rises well above it the buzzer plays the three-beep pattern (T3) that real smoke alarms use while the red LED flashes with the beeps. The green LED blinks while warming up and stays on once the alarm is armed. It teaches reading an analog sensor against its own clean air value, using two separate thresholds so the alarm does not flicker at the edge, and playing a sound pattern with millis() while still taking readings. No extra library needed. This is a learning project; it does not replace a certified smoke and gas alarm at home.Open project
• RFID Card Door LockIntermediate60 minA door lock that opens with a card or key fob you have introduced: the RC522 reader reads the card's number, and if it is known the green LED lights up, a short beep sounds and the servo turns the latch and opens the door for 5 seconds; an unknown card lights the red LED and sounds a long beep. The first card you scan becomes the master card: scanning it opens adding mode for 10 seconds, and a new card scanned meanwhile is added, a known one removed. The cards are kept in the Arduino's EEPROM memory, so they are not forgotten when the power goes. It teaches talking to a module over SPI, comparing card numbers, keeping a small list in EEPROM, and letting a mode close by itself. Install "MFRC522" from the Library Manager; Servo and EEPROM come with the Arduino IDE. This is a learning project; do not use it as a real door's only lock.Open project
• Joystick Snake GameIntermediate45 minThe classic snake game on an 8x8 LED screen: you steer the snake with the joystick, and when it eats the blinking food it grows one cell longer, gets a little faster and the buzzer gives a short beep. The screen is small, so the snake leaves one edge and comes back in at the other; when it runs into its own body the game is over, three falling notes play, your score shows on the screen in digits, and pressing the joystick's button starts a new game. It teaches reading an analog joystick and turning it into a direction, keeping a game in arrays (the snake's cells), setting the game's speed with millis(), and driving a MAX7219 LED matrix with a few wires. Install "LedControl" from the Library Manager.Open project
• Kitchen TimerBeginner30 minA kitchen timer for tea, eggs or pasta: you set the time by turning the rotary encoder, and the 4-digit display shows it as minutes:seconds. Press the knob and the countdown starts, with the colon in the middle blinking once a second; press again to pause, once more to carry on where it stopped, and hold it down to go back to the time you set. When the time is up the buzzer beeps three times a second and the display blinks; a press silences it and the same time is ready to run again. It teaches reading a rotary encoder's direction with an interrupt, telling a short press from a long one on a single button, counting down with millis(), and driving a TM1637 display with two wires. Install "TM1637" (Avishay Orpaz) from the Library Manager.Open project
• Digital Spirit LevelIntermediate45 minA project that turns the breadboard itself into a spirit level: the MPU6050's accelerometer measures which way gravity pulls, and the Arduino works out the tilt on two axes in degrees. On the left of the OLED a bubble runs to the high side like in a real spirit level, and on the right the X and Y tilt are written; once both are under half a degree the screen says "LEVEL" and the buzzer gives two short beeps. It teaches using a sensor without a library by reading its registers directly, working out an angle from gravity (atan2), smoothing a jittery reading, and putting two I2C modules on one line. Install "Adafruit SSD1306" and "Adafruit GFX" from the Library Manager.Open project
• Flame-Sensing Fire AlarmBeginner30 minA fire alarm that recognises a flame by the infrared light it gives off: when the flame sensor sees a lighter or a candle flame, the buzzer plays a rising siren and the red and blue LEDs flash in turn like a fire engine's lights. While idle, the blue LED blinks briefly every 2 seconds to show the alarm is on watch. The alarm does not sound until a flame has lasted half a second, so a single spark or glint does not set it off, and it keeps sounding for 3 seconds after the flame is out. It teaches smoothing the on-and-off digital signal of a flickering flame, filtering out short flashes with a time condition, and playing a siren with millis() while reading the sensor. No extra library is needed. This is a learning project; it does not replace an approved smoke detector at home.Open project
• Rain Alert and Automatic WindowBeginner40 minA setup that sounds an alert and closes the window by itself when it starts to rain: when water drops land on the rain sensor's plate, the buzzer plays a ding-dong three times, then a servo slowly closes the window. Some time after the plate dries, the window opens again. The sensor board is powered from one of the Arduino's pins and switched on only while measuring, so the plate does not corrode by electrolysis. It teaches turning an analog reading into a percentage, using two separate thresholds for rain and dry, timing a period (that starts over if the plate gets wet again) and turning a servo slowly, one step at a time. The Servo library comes with the Arduino IDE; there is nothing to install.Open project
• Waterproof Thermometer (Aquarium / Tea)Beginner30 minA thermometer that measures water temperature with a waterproof DS18B20 probe and shows it on a 4-digit display as "24°C". When the temperature leaves the allowed range the buzzer sounds and the display blinks: three fast, high beeps when too hot, a slow, low beep when too cold, so you can tell which by ear alone. It comes set to 23-28 °C for an aquarium; for tea, set the lower limit to 60 °C and it beeps once the tea has cooled enough to drink. It teaches 1-Wire communication and the pull-up resistor, not making the program wait while a reading is taken, and leaving a margin so the alarm does not flicker at the limit. The DallasTemperature and TM1637 libraries are installed from the Library Manager.Open project