| 摘要 |
<p>PURPOSE:To reduce the fluctuation of the voltage across a printed wiring board and, at the same time, to cope with an increase in the number of power supply layers due to an increase in the quantity of electric current by providing power supply fluctuation uniformizing layers. CONSTITUTION:Electric power is supplied to loads 4 of an LSI, resistance, etc., mounted on a printed wiring board 1 through internal power supply layers 3 connected with a power feeding pad 2 to which feeders are connected from a power source at the peripheral edge section of the board 1. The uppermost layer 3 which is the nearest to the loads forms a uniformizing pattern 6 which is divided into load 4 mounting areas. Therefore, the voltage fluctuation of the printed board is reduced and an increase in the number of power supply layers due to an increase in the quantity of electric current can well be coped with, since the the pattern 6 can be regarded as a load which is low in the resistance of its power supply system and less in electric current.</p> |
