| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a printed wiring board and a printed circuit board unit that prevents effect of difference in permittivity with a simple structure. <P>SOLUTION: In the printed wiring board 14, glass fiber yarns 26 are impregnated with resin. Gaps between the glass fiber yarns 26 are thereby filled with resin. The width of wiring patterns 16 and 17 is set wider than the interval P1 of the centerlines of the glass fiber yarns 26, so that the wiring patterns 16 and 17 are covered with both glass fibers and resin without fail. The ratio of glass fibers and resin covering the wiring patterns 16 and 17 is made as uniform as possible. Consequently, impact of difference in permittivity between the fibers and resin is controlled more than before by the wiring patterns 16 and 17. Variations in characteristics impedance is thereby reduced by a simple structure. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
