The piezoelectric ceramic sensor is used for ultrasonic beauty film with a diameter of 16mm, a resonance frequency of Fs 5±7%MHz, and a material of 0.41mm thickness. PZT4 has two electrodes on one side.
A buzzer or beeper is an audio signaling device, which may be mechanical, electromechanical, or piezoelectric. Piezoelectric buzzers, or piezo buzzers, are devided into 3 main types: passvie piezo buzzers, active piezo buzzers and self drive piezo buzzers.
Passive piezo buzzers, also known as piezo transducers, consist of a casing, a piezo element and a terminal, and you need external driving signal to operate the buzzer, therefore, with greater range of flexibility of frequencies when designing PCB circuit.
