An electronic device is described comprising at least one chip enclosed in a package, in turn provided with a metallic structure or leadframe having a plurality of connection pins, this chip having at least one first contact realized on a first face and at least one second contact realized on a second and opposite face of this chip. The chip comprises at least one through via crossing the whole section of the chip as well as a metallic layer extending from the second contact arranged on the first face, along walls of the at least one through via up to the second and opposite face in correspondence with an additional pad. The electronic device comprises at least one interconnection layer for the electrical and mechanical connection between the chip and the metallic structure having at least one portion realized in correspondence with the at least one through via so as to bring the second contact placed on the second face of the chip back on its first face. An assembly process of such an electronic device is also described.