A piezoelectric device for generating an electrical voltage, comprises a vibrating plate having a portion integral with a fixed support and at least one free end capable of moving under the effect of a mechanical pulse, and at least one piezoelectric element attached to one face of the plate so as to deform under the effect of the oscillations of the plate that result from said mechanical pulse, thus generating an electrical voltage.The plate has a U-shaped or V-shaped general configuration, possessing two substantially planar branches joined by a curved linking portion integral with the support.