The acoustic range of piezoelectric ceramic element buzzer and the audio design of piezoelectric ceramic buzzer

 Piezo element film buzzer In general, a human's audio range is between approximately 20 Hz and 20 kHz. The most audible audio is 2kHz to 4kHz.Therefore, most piezoelectric sound elements are used in this audio range. At the same time, the buzzer resonance frequency (f0) is generally selected to be in the same range. The resonant frequency depends on the method used to support the piezoelectric element diaphragm.

Normally, a piezoelectric diaphragm is installed in the resonance chamber to generate a high sound pressure. Using the formula (1) (Hermholtz formula), the resonant frequency (fcav) of the resonance chamber can be calculated. Since the piezoelectric diaphragm and the resonance chamber have appropriate resonance frequencies, respectively (f0) and (fcav), it is possible to increase the sound pressure at a specific frequency and obtain a specific bandwidth by controlling the positions.PZT piezo bimorph buzzer is widely used in the clock, calculator, telephone, washing machine, various alarms (burglar alarm, etc.)

Piezoelectric ceramic buzzer is a device used in piezoelectric ceramic sheets. It is more common to form titanium piezoelectric ceramic sheets (pzt) sintered with zirconium and lead oxides. Since the human ear is most sensitive to the audio signal of 3khz, the resonant frequency of the piezo bimorph buzzer is usually designed during production. Around 3khz. In order to improve the low frequency response, a double diaphragm structure is generally employed.