| 摘要 |
<p>PURPOSE:To provide a printed circuit board in which a strain of a transmission signal waveform due to a signal interference between signal wirings and a capacitance between the signal wiring and a ground copper foil arranged on a rear surface is suppressed in the board having the wirings arranged in parallel. CONSTITUTION:A plurality of bus wirings 2 provided in parallel on a front surface of a printed circuit board 1b connect a central processor 3 to an input/ output unit 4. A ground copper foil having a plurality of copper foil lacking parts 6 corresponding to arranging positions of the wirings 2 is provided on a rear surface of the board 1b. Thus, a capacitance formed of the wirings 2, the dielectric board and the foil is reduced to decrease a strain of a transmission signal waveform.</p> |
