What Are Buzzers?
The SOH08 Buzzers are indispensable audio signaling devices in the electronic components industry, widely used across consumer electronics, automotive systems, security solutions, medical devices, and industrial automation. As smart devices, the Internet of Things (IoT), and new energy vehicles continue to advance, the demand for buzzers is steadily rising, with technologies evolving to enhance user interaction and safety features. This article provides a comprehensive guide to buzzers, covering their definition, working principles, types, key characteristics, advantages, and typical applications.
Catalog
I. What Are Buzzers?
A buzzer, also known as a sounder, is an electroacoustic component that converts electrical signals into audible sound signals. Typically powered by DC voltage, a buzzer emits a “beep” or other tone to provide alerts, warnings, or operational feedback. In circuit diagrams, buzzers are often represented by symbols such as “H” or “HA.”
Structurally and functionally, buzzers are mainly categorized into two types:
· Electromagnetic Buzzers: These use coils and diaphragms to produce sound through mechanical vibrations.
· Piezoelectric Buzzers: These utilize a piezoelectric ceramic that vibrates when subjected to an alternating current, generating sound.
II. Work Principles
· Electromagnetic Buzzers: These buzzers consist of an oscillator, magnet, coil, and diaphragm. When powered, the coil generates an alternating magnetic field that attracts and releases the diaphragm in cycles, producing sound. They typically operate within a frequency range of 2 to 4 kHz.
· Piezoelectric Buzzers: These operate via the piezoelectric effect. When alternating voltage is applied to a piezoelectric ceramic disc, it deforms and vibrates, creating sound through a resonant cavity. Their standard frequency range is between 1.5 to 6 kHz, with an operating voltage between 3 to 250V and a current below 30 mA.
Active vs Passive Buzzers
· Active Buzzers: Equipped with an internal oscillator, they emit sound with direct DC input and have a fixed frequency.
· Passive Buzzers: Lacking an oscillator, they require an external signal like PWM or square waves for sound generation, allowing flexible frequency and tone control.
III. Features and Advantages
· Low Power Consumption: Particularly for piezoelectric buzzers, making them ideal for portable and energy-efficient devices.
· Compact Size: Available in both SMD and DIP packages, easy to integrate into space-constrained PCBs.
· High Reliability and Long Lifespan: Especially piezoelectric types, which offer excellent shock resistance and high-temperature tolerance.
· Fast Response Time: Capable of responding within milliseconds, suitable for high-frequency alerts or alarms.
· Wide Frequency and Sound Pressure Range: Accommodates diverse application requirements for volume and pitch.
· Simple Driving Circuit: Active buzzers can sound with a direct power connection, requiring no complex circuitry.
IV. Applications
Buzzers are versatile and integrated into nearly all types of electronic devices:
· Consumer Electronics and Computers: Timers, printers, motherboard boot sounds, etc.
· Automotive Electronics: Seatbelt reminders, reverse parking alerts, dashboard indicators.
· Security Systems: Smoke detectors, intrusion alarms.
· Medical Devices and Industrial Controls: For endpoint notifications and system alerts.
· Toys and Educational Electronics: Providing sound feedback in interactive projects.
· Measurement Tools and DIY Kits: Water level alarms, component testing, embedded system notifications.
V. Selection Suggestions
When selecting a buzzer, consider these factors:
· Type: Active for easy integration, passive for customizable tones.
· Driving Method: Choose between direct DC input or square wave drive.
· Operating Voltage and Current: Ensure compatibility with the system’s power supply.
· Package Type: Select DIP, SMD, or wired options based on PCB design.
· Sound Pressure Level and Frequency Range: Verify they meet the desired auditory output for the application environment.
Additionally, when using transistor-driven circuits, it's recommended to include a flyback diode and filter capacitor to protect the MCU output.
VI. Conclusion
Buzzers, though small, play a crucial role in electronic products. Market research shows steady growth in the buzzer sector, with piezoelectric buzzers gaining prominence due to their low power and high efficiency—especially in new energy vehicles, smart wearables, and IoT devices. In the future, buzzers that offer higher integration, smaller sizes, and better sound quality are expected to dominate the market.
