Patent ID: 8243465

Claim:
A device, comprising: a package substrate comprising a first power supply terminal, a second power supply terminal, a signal terminal, and a plurality of conductive layers; a first semiconductor chip located above the package substrate, and the semiconductor chip comprising a first circuit operating on a first power supply voltage, a second circuit operating on a second power supply voltage and generating an output signal, a first pad supplying the first circuit with a first power supply potential as one of potentials of the first power supply voltage and a second pad supplying the second circuit with a second power supply potential as one of potentials of the second power supply voltage, a signal pad receiving the output signal from the second circuit; a first additional substrate located above the first semiconductor chip, the first additional substrate comprising a first wiring layer formed on an opposite side to the first semiconductor chip; a first power supply path electrically connecting the first power supply terminal of the package substrate to the first wiring layer of the first additional substrate; a second power supply path electrically connecting the first wiring layer of the first additional substrate to the first pad of the first semiconductor chip, the second conductive path being free from including any one of the conductive layers of the package substrate between the first wiring layer of the first additional substrate and the first pad of the first semiconductor chip; a third power supply path electrically connecting the second power supply terminal of the package substrate to the second pad of the first semiconductor chip; and a signal path electrically connecting the signal terminal of the package substrate to the signal pad of the first semiconductor chip.