| 摘要 |
<p>PROBLEM TO BE SOLVED: To greatly reduce generation of radiation noise permeating into a power source layer and a ground layer of a multilayer printed circuit board the noise of which is caused by the high frequency power source current of an integrated circuit element. SOLUTION: In this multilayer printed circuit board, a power source layer, a ground layer and a signal layer are mutually laminated, interposing insulating layers, and various kinds of integrated circuit elements are mounted on the surface layer. In this case, bypass capacitors 30 inserted between the power source layer and the ground layer are arranged on each equally divided region, where the power source layer and the ground layer face each other is divided equally by the same shape and the same area. The shape of the equally divided region is made into a square. The bypass capacitors 30 are arranged at almost the centers of the equally divided regions. The value of the capacitance of the capacitor 30 is set larger than the value of board capacitance formed in the region where the power source layer and the ground layer face each other, and all the values of combined inductance of the bypass capacitors 30 are set equal.</p> |
