A micropump device is formed in a monolithic semiconductor body integrating a plurality of actuator elements arranged side-by-side. Each actuator element has a first chamber extending at a distance from a first face of the monolithic body; a membrane arranged between the first face and the first chamber; a piezoelectric element extending on the first face over the membrane; a second chamber, arranged between the first chamber and a second face of the monolithic body; a fluidic inlet path fluidically connecting the second chamber with the outside of the monolithic body; and a fluid outlet opening extending in a transverse direction in the monolithic body from the second face as far as the second chamber, through the first chamber. The monolithic formation of the actuator elements and the possibility of driving the actuator elements at different voltages enable precise adjustment of flows, from very low values to high values.