Joy-It Vibrations sensor

This module is equipped with a ceramic vibration sensor which is a vibration analogue signal. The sensor may have different vibrations measure thickness.

Vibrations that affect the sensor generate a voltage signal due to the piezoelectric effect depending on the strength of the vibration.
Therefore, you do not need a supply voltage for the sensor, but only the voltage at the signal pin of the sensor has to be measured by using an analog-digital converter.