Piezoelectric buzzer and the structure Principles of presentation
Piezoelectric film buzz is very high-pressure after the piezoelectric ceramics adhesive vibration in the metal-on-chip. When the voltage to join the exchange, because of piezoelectric effect, the mechanical deformation resulting from stretching and shrinkage of the use of the properties of metal so that the vibration and sound.
Piezoelectric buzzer metal vibration
Feedback to make the distinction between the way piezoelectric film would be divided into buzz-buzz-chip feedback (Self-excited) with no feedback buzz-on-chip (outside-excitation) two. When the feedback-film buzz with positive feedback oscillation circuit will have a cavity with the same frequency tone; feedback and no-film buzz can with the external oscillator circuit, to choose any frequency sounds.
Piezoelectric buzzer oscillation circuit
The following is the buzz of two piezoelectric film fixed:
a. external support – the buzz film at the outer edge of fixed-cavity resonance, not to adopt the general feedback buzz-on-chip, and its buzz with film resonator with frequency, there will be a higher sound pressure output By the external shocks have a circuit to promote signal, so that the buzzer sounds.
Piezoelectric buzzer fixed one way
b. node support – will be fixed on the buzz about films with the ceramic piece with a diameter the size of the ring structure. If properly designed cavity, and with the correct frequency of feedback-film buzz with the feedback circuit is, will be able to have a greater voice in the right frequency and voltage.
Piezoelectric buzzer fixed two ways
Above are two ways to take silicone adhesive film buzz in organizations.
