| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayered circuit board which is capable of reducing electromagnetic interference sufficiently by decreasing the reflection of high- speed signals. SOLUTION: A first, second, third, fourth, and fifth insulating board, a first, a second, a third, and a fourth signal wire layer, a grounding wire layer, and a power supply wire layer are formed into a circuit board of thickness 1.6 mm or so by pressure welding. The first signal wire layer has a first resistance value to the grounding wire layer, the second signal wire layer has a second resistance value to the grounding wire layer and the power supply wire layer, the third signal wire layer has a third resistance value to the grounding wire layer and the power supply wire layer, and the fourth signal wire layer has a fourth resistance value to the power supply wire layer. The insulating boards are so set as to be within an optimal range, so that the first to the fourth resistance value are so set as to be 49.5 to 60.5Ωrespectively. |
