The KY-012 Active Buzzer Module is a compact, ready-to-use sound output board designed for Arduino, ESP32, Raspberry Pi, STM32, and other microcontroller projects. Unlike passive buzzers that require an external frequency signal to produce sound, the KY-012 uses an active buzzer with a built-in oscillator — simply apply power, and it produces a fixed-frequency tone. This makes it the simplest way to add audible feedback, alarms, and notifications to your projects without any complex programming or external circuitry.
At the heart of the module is an active piezoelectric buzzer with an integrated oscillation circuit. When powered, the internal oscillator drives the piezo element at its designed resonant frequency, producing a loud, clear tone — typically around 2.3kHz to 3.5kHz. The sound output is sufficient for most indoor applications, including alarms, notifications, and user feedback. The active design means you don’t need to generate a PWM signal — just set a digital pin HIGH to turn the buzzer on, and LOW to turn it off.
The module features a 3-pin interface (VCC, GND, I/O or S) for easy connection to microcontrollers. The signal pin accepts a digital signal — HIGH turns the buzzer on, LOW turns it off. The compact form factor with mounting holes allows easy integration into alarm systems, notification devices, and interactive projects. The module includes onboard current-limiting circuitry to protect the buzzer and the microcontroller’s output pin.
The KY-012 operates from a 3.3V to 5V DC supply, making it compatible with both modern low-power microcontrollers and traditional 5V systems. The low power consumption makes it suitable for battery-powered alarm and notification projects.
The KY-012 is widely used in alarm systems, notification devices, doorbells, timers, game controllers, interactive toys, security systems, industrial control panels, and educational STEM projects. It is also popular in DIY electronics and maker projects where audible feedback is required.
Important Note: The KY-012 is an active buzzer — it produces a fixed tone when powered. It cannot produce different frequencies or play melodies. For variable tones or music, use a passive buzzer (such as the KY-006) instead, which requires a PWM signal. The buzzer is not waterproof and should be kept dry. Avoid continuous operation at high volume for extended periods, as this may cause the buzzer to overheat or degrade over time.
Whether you are building an alarm system, a notification device, or an interactive project, the KY-012 Active Buzzer Module provides a reliable, simple solution for audible feedback. It is suitable for individual makers, students, and businesses purchasing in bulk for product development or educational programs.
Features
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Active buzzer with built-in oscillator — Produces sound when powered; no PWM required
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Simple digital control — HIGH turns buzzer on, LOW turns it off
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Loud, clear tone — Approximately 2.3kHz to 3.5kHz output
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3-pin interface — VCC, GND, I/O for easy connection
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Wide voltage range — 3.3V to 5V DC, compatible with Arduino, ESP32, Raspberry Pi
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Onboard current-limiting circuitry — Protects buzzer and microcontroller
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Low power consumption — Suitable for battery-powered applications
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Compact form factor — With mounting holes for easy integration
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Wide application range — Alarms, notifications, doorbells, timers, interactive toys
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Cost-effective — Affordable solution for sound output in volume production
Technical Specifications
| # | Parameter | Specification |
|---|---|---|
| 1 | Module Model | KY-012 |
| 2 | Buzzer Type | Active piezoelectric buzzer |
| 3 | Operating Voltage | 3.3V – 5V DC |
| 4 | Sound Output | Fixed tone, approximately 2.3kHz – 3.5kHz |
| 5 | Control Method | Digital (HIGH = ON, LOW = OFF) |
| 6 | Current Consumption | ~20mA (typical) |
| 7 | Pin Count | 3 pins (VCC, GND, I/O) |
| 8 | Module Dimensions | Compact PCB with mounting holes |


























