Their current consumption is typically less than 10mA. Piezo buzzers use minimal current so draw less power.Size – they are small, compact devices able to produce an audible alert or alarm for a variety of applications.This movement produces sound.Ī good quality speaker produces a very similar sound to the electrical signal sent into it. The voice coil moves up and down as it is attracted and repelled by the magnet which in turn moves the speaker cone which the coil is attached to. This interacts with the magnetic field generated by the permanent magnet within the speaker. When this electrical energy is activated it moves though the coil of wire creating a magnetic field. As mentioned, they require an AC electrical signal to operate. Speakers contain a magnet, voice coil and diaphragm or cone. As current flows through the coil a fluctuating magnetic field is produced which causes the diaphragm to vibrate and emit sound. When a voltage is applied, the diaphragm is pulled towards the magnet. This movement of the disc generates sound.Įlectromechanical buzzer – contains a magnet, diaphragm and coil. Piezo buzzer - contains a piezo ceramic element which moves up and down when a voltage is applied. How they work is explained in simple terms below: This makes them a good option for voice or music reproduction.Īs mentioned, typically buzzers are either piezo or electro-mechanical devices. A speaker reproduces the audio signal it receives so the sound going out is similar to the sound going in. Speakers use AC voltage to generate sound and require additional circuitry such as an audio amplifier. Those driven by AC voltage, Audio Transducers, need additional circuitry to produce a sound. Buzzers driven by DC voltage, Audio Indicators, contain an internal drive circuit. This sound is usually a single buzz tone, although dual tone and fast/slow pulse sounders are available. They are piezo or electro-mechanical devices that produce a sound when an AC or DC voltage is applied. So, when designing an application that requires an audible alert for user input or alarm function, which should you choose? How do you decided between a buzzer vs speaker? What is a buzzer?īuzzers are also known as sounders, piezo buzzers, audible alarms, audio indicators and piezo transducers. Most common usage is as vibration or tap sensor.Buzzers and Speakers are transducers that convert electrical energy into sound. Be aware: these voltages may be high enough to destroy the input of a micro controller it is attached to.

If you use a piezo transducer as sensor it translates mechanical deformations into measurable voltages. Most common use for piezo speakers is as buzzer. The advantage of a piezo speaker is that these speakers can be very thin, are magnet free, and moisture proof. So don’t use a piezo speaker for frequencies lower than 500Hz or so. The frequency response is usually limited to a few kHz. The piezo speaker has a high impedance (resistance for AC signals) and can be driven by an Arduino or small transistor easily. That’s why piezo-crystal or piezoelectric transducer is actually a better name (transducer it can be a sensor as well as an actuator). You can also use a piezo crystal as a sensor. When applying a voltage, the crystal deforms, which in case of a piezo speaker, produces a sound that we can hear. When compressing a piezo crystal, a voltage appears on its terminals. Piezo is used in many different applications ranging from electric lighters and fire alarms to echo scanners. Piezo refers to a ceramic or crystal material with piezoelectric properties. Piezo refers to the material of which the speaker is made of.

Piezo speakers