| 摘要 |
<p>PURPOSE:To reduce noise and provide a compact printed board without using many EMI filters. CONSTITUTION:A power supply pattern 7 and a first inner layer pattern block formed with a specified interval d in a substrate 100 are connected each other through a power supply pattern 7 and EMI filter 11a. The block 5 is further connected with all of a plurality of power supply terminals 2 in a digital IC 1. Therefore, the noise that is generated in the IC 1, transmitted through the terminals 2 and gathered into the block 5 is reduced by the filter 11a. Further, since the block 5 is formed in a manner to be overlapped on the mounting position of the IC 1, the substrate 100 is made compact. In addition, the number of filters can be decreased by gathering the noise from the terminals 2 into the block 5 and filtering the noise with the filter 11a.</p> |
