| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the influence on a high frequency signal, of the parasitic capacitance generated on a multilayered printed board including a high frequency circuit such as a signal processing circuit in a passenger detection system of a vehicle. SOLUTION: In a multilayered printed board 1 formed by laminating the upper, intermediate and lower three printed boards 2, 3, 4, a signal pattern 16 in which a high frequency signal flows and the shield patterns 17a, 17b on both sides of the signal pattern 16, are formed on the intermediate printed board 3. Further the shield patterns 17c, 17d of the width corresponding to the signal pattern 16 and the shield patterns 17a, 17b, are formed on the upper printed board 2 and the lower printed board 4 to surround the signal pattern 16 by the shield patterns 17a-17d located on both sides and upper and lower sides, and a signal of the same level as that of the signal pattern 16 is applied to the shield patterns through a buffer circuit.</p> |
