Micro & Mini Loudspeaker Selection
Buzzers are acoustic signaling transducers that emit an audio tone when a voltage is applied. They are used in many electronic devices typically to deliver information or warnings to users. There are a few practical considerations to bear in mind for selecting the correct buzzer product for your application.
At the outset, there may be physical constraints for a given application in terms of transducer size, panel, or other mounting locations, as well as required SPL (sound pressure level) output.
There is also the choice to make regarding through-hole PTH or surface-mount SMT variants.
There are two main buzzer technologies: magnetic and piezo. With modern drive circuits and materials, differences between the technologies have reduced dramatically; however, before these improvements, magnetic buzzers carried the advantage of lower operating voltages but required higher operating currents. Piezoelectric versions had lower operating currents but greater operating voltages. At Summit the differences in operation voltage, currents and efficiencies for the magnetic and piezo buzzers is negligible - both have equivalent characteristics in terms of voltage, current, and sound output making the choice more about other factors such as tone and form factors. Summit piezo devices do have a larger voltage operating range – typically from 1 up to 25v, which can be useful for some use cases.
Magnetic buzzers work on the operating principle of a current being driven through a winding to displace a diaphragm with a magnetic disk on it. When the current is not present the diaphragm returns to its original position, creating a difference in air pressure. An oscillating field is applied to the winding to produce a sound tone. Although a voltage is applied, magnetic buzzers are current-driven devices. The sound produced is typically between 2-4Khz. In terms of use cases, they have a loud and penetrating sound output and are suitable for many different diverse applications including alarms, industrial machines and emergency notification systems. They are also available in compact form factors with variants for harsher environmental conditions.
Piezo buzzers use a piezoelectric crystal such as quartz as the driver mechanism. When a voltage is applied the crystal deforms which moves a diaphragm. When the voltage is removed the crystal and diaphragm return to their original shape and position. They are voltage driven devices and generally have a frequency output of 1.5 kHz to 4 kHz, with Summit versions tuned for operation at 4 kHz.
Summit has an extensive range of both magnetic and piezo buzzer products available with frequency outputs from 2-4 kHz and with operating voltages from 1-30v. Whatever your buzzer requirements, we’ve got it covered.
