Patent ID: 7088591

Claim:
A multi-layer printed circuit board for mounting electronic parts on it, comprising: a first signal layer formed on an obverse surface of said multi-layer printed circuit board; a ground layer arranged at a position next to said first signal layer; an electronic power source layer arranged at a position next to said ground layer; and a second signal layer formed on a reverse surface of said multi-layer printed circuit board; wherein a first ground pattern is formed around a peripheral area of said first signal layer, while a second ground pattern is formed around a peripheral area of said second signal layer; and wherein said first ground pattern and said second ground pattern are electrically coupled to each other by a plurality of through holes, and said multi-layer printed circuit board is installed on an electro-conductive housing in such a manner that a substantially whole area of said second ground pattern electrically contacts a mounting area of said electro-conductive housing, said mounting area being an electro-conductive area continuously coupled to said electro-conductive housing; and wherein a snubber circuit, being a serial connection of a resistor and a capacitor, is coupled between said ground layer and said electronic power source layer.