| 摘要 |
PURPOSE:To design a circuit pattern of printed board with a free conception by arbitrarily setting the fluctuation of characteristic impedances resulting from the widths of different signal conductors based on the opening areas of ground conductors. CONSTITUTION:Capacitances exist between signal conductors 4 and ground conductors 1 and the capacitances become impedance elements. Impedance elements also exist between respective signal conductors 4. The characteristic impedances generated between respective signal conductors 4 and between the conductors 4 and ground conductors 1 on both sides of the conductors 4 vary depending upon the distances and areas thereof. When the areas and shapes of the openings 2 deciding the width of the ground conductors 1 fluctuate in the direction in which the characteristic impedances of the conductors 4 are uniformized, the fluctuation of the characteristic impedances of the conductors 4 can be eliminated. The widths of the conductors 4 and sizes of the openings 2 of the conductors 1 are controlled based on the relation among the sizes of the openings 2, widths of the conductors 4, and characteristic impedances of the conductors 4. |
