| 摘要 |
<p>PROBLEM TO BE SOLVED: To solve the problem that electric noise is increased in each signal wiring, and the degree of freedom in wiring and the number of the signal wiring are reduced in the signal wiring in a multilayer wiring board. SOLUTION: This multilayer wiring board has an insulating board 2 comprising insulating layers 2a to 2d, a buried microstrip line section 6 comprising a group 3 of the signal wiring having first wiring length that is covered with an insulating covering layer 5 and a power supply layer or a grounding layer 4 formed while it opposes the group 3 of the signal wiring, and a strip line section 9 comprising a group 7 of the signal wiring having second wiring length and the power supply layer or grounding layers 4 and 8 formed at the upper and lower sections while they oppose the group 6 of the signal wiring. Also, 0.8×(0.670/εr-0.525)×e -2x(b+t)/h}+1]1/2<=L2/L 1<=1.2×[(0.670/εr-0.525)×e -2x(b+t)/h}+1]1/2 (in this case, L1>L2) should be met in the multilayer wiring board 1, thus reducing the electric noise, and hence improving the degree of freedom in the wiring and the number of the signal wiring.</p> |
