| 摘要 |
<p>PURPOSE:To provide a printed board provided with a by-pass capacitor for free layout close to the components mounted in high density. CONSTITUTION:The number '1' represents the whole of a printed board. '2' shows glass epoxy insulating material (dielectric constant: approx. 4.6) between layers, and the area between the layers has a thickness of 0.1mm. '3' represents a +5V power supply layer, 70mum in thickness, of the second layer. '4' is a ground layer, 70mum thick, of the seventh layer, and '5' and '6' are patterns of the fourth and fifth layers, respectively. '7' represents the through hole for connection between the power supply layer 3 and the pattern 5, and '8' shows the through hole for connection between the ground layer 4 and the pattern 6. The pattern 5 is a square of 2cm and has a projection for connecting the through holes. The pattern 6 has the same shape except that its projection is different in position from that in the patter 5. Seen through from above, the patterns 5, 6 are overlapped with each other. The pattern 5, 6 form a by- pass capacitor of 160pF for systems of 2-3GHz.</p> |
