A semiconductor device includes a first semiconductor chip located over a substrate; and a second semiconductor chip located over the first semiconductor chip, wherein the first semiconductor chip includes a first internal power supply generation circuit that generates a first internal power supply voltage supplied to a first internal circuit; a first penetration electrode formed from an upper surface of the first semiconductor chip to an underside of the first semiconductor chip and electrically connected to the first internal power supply generation circuit; a first reference voltage generation circuit that generates a first reference voltage; and a second penetration electrode formed from the upper surface of the first semiconductor chip to the underside of the first semiconductor chip and electrically connected to the first reference voltage generation circuit.