| 摘要 |
PURPOSE:To increase the effect of a guard pattern for enabling a noise signal to escape from a power supply layer or a ground layer by electrically connecting the power supply layer surrounding by a non-conduction line to the power supply layer outside the non-conduction line at one or more points. CONSTITUTION:Guard patterns 2 are located at a position opposing a power supply layer or a ground layer (a power supply layer 3) formed in a second layer S2. The guard patterns 2 and a discontinuous non-conduction line 6 forming the contour of the power supply layer 3 in the second layer S opposing a region surrounded by the guard patterns are provided. Also, a through hole 7 is provided to connect the power supply layer 3 in the second layer S2 surrounded by the non-conduction line 6 to each guard pattern 2. Further, the power supply layer 3 surrounded by the non-conduction line 6 is electrically connected to the power supply layer 3 outside the non-conduction line 6 at least at one point, thus improving the effect of the guard pattern for letting a noise signal to be escaped to the power supply layer 3 or the ground layer. |
