| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayer circuit board which can accomplish impedance matching and reduce fast signal reflection and electromagnetic interference. SOLUTION: The multilayer circuit board comprises first to seventh insulation substrates subject to superposition arrangement, first to fifth signal wiring layers and first and second ground wiring layers and a power supply wiring layer, the thickness of the first and seventh insulation substrates is 63.5 to 165.1 μm, the thickness of the second, fourth and sixth insulation substrates is 76.2 to 228.6 μm and the thickness of the third and fifth insulation substrates is 76.2 to 584.2 μm, the first signal wiring layer has a first resistance between it and the first ground wiring layer, the second signal wiring layer has a second resistance between the first ground wiring layer and a power supply wiring layer, a third signal wiring layer has a third resistance between the first ground wiring layer and the power supply wiring layer, the fourth signal wiring layer has a fourth resistance between the second ground wiring layer and the power supply wiring layer, and the fifth signal wiring layer has a fifth resistance between it and the second ground wiring layer, and the resistances are limited to 49.5 to 60.5 Ω. |
