Patent ID: 7816757

Claim:
A semiconductor device comprising: a digital semiconductor element connected with a power connection terminal and a ground connection terminal; an analog semiconductor element connected with a power connection terminal and a ground connection terminal; a wiring board mounted with the digital semiconductor element and the analog semiconductor element; and a plurality of external terminals connected to the wiring board, wherein the wiring board includes an EBG (Electromagnetic Band Gap) layer formed by arranging a plurality of unit wiring patterns each of which is composed of two wiring patterns having different impedances over a flat plane, a ground layer, a power layer for a digital element connected to one end of the EBG layer, and a power layer for an analog element connected to the other end of the EBG layer, wherein the ground connection terminal for the digital semiconductor element and the ground connection terminal for the analog semiconductor element are connected to the ground layer of the wiring board, wherein the power connection terminal for the digital semiconductor element is connected to the power layer for the digital element of the wiring board, and wherein the power connection terminal for the analog semiconductor element is connected to the power layer for analog element of the wiring board.