Abstract: A circuit board having a printed capacitor whose capacitance is easily adjusted includes a plurality of through-holes arranged in arrays and electrically connected to each other via conductive films. Therefore, first and second electrode portions are arranged to oppose each other, and form a printed capacitor. The capacitance of the capacitor can be adjusted by the number and diameter of through-holes, and the interval between each two adjacent through-holes. Therefore, even when a large-capacitance capacitor is to be formed, the printed capacitor can be rendered compact.

Abstract: A printed circuit board capable of suppressing radiation noise efficiently includes a first conductive layer where a plurality of power lines are provided at predetermined spacing along one direction, a second conductive layer where a plurality of power lines are provided at predetermined spacing along a direction orthogonal to the one direction, and a plurality of plated through holes for connecting the power lines on the first conductive layer and the power lines on the second conductive layer at the overlapping points of those lines. The power lines contain thin lines and thick lines spaced between a plurality of the thin lines. The predetermined spacing is determined based on a rising time or falling time of the output signal of the IC to be mounted on the circuit board.