Piezoelectric buzzers are used in music CARDS, electronic doorbells, electronic toys and other small electronic devices as sound devices
Piezoelectric buzzers can be driven by a drive circuit in the following two ways:
Self-excited oscillation is a way of generating sound waves by oscillating at the resonance point
no self-excited oscillation is a way of generating sound waves at frequencies far away from the resonant point
The piezoelectric buzzer can be as loud as 70 decibels /20cm
Yes. Active buzzer, internal oscillation, drive circuit. Add power can ring, the advantage is to use up save trouble, the disadvantage is that the frequency is fixed, only a single tone. Passive buzzers, like horns, require alternating audio voltages to produce sound, and can also produce sounds of different frequencies.
Piezoelectric buzzer is mainly composed of multivibrator, piezoelectric buzzer, impedance matcher, resonator and shell
Piezoelectric buzzers can be divided into two types: feedback buzzer (self-excitation) and non-feedback buzzer (external excitation). When the feedback buzzer is combined with the positive feedback oscillator circuit, a single sound with the same resonant cavity frequency will be produced.The non-feedback buzzer can be paired with an external oscillating circuit to produce sound at any frequency