Patent ID: 8402422

Claim:
A wiring design device to conduct wiring design on a printed wiring board that includes a plurality of conductive layers, the wiring design device comprising: a noise contaminating part extracting unit to extract a part in a condition where noise contaminates a signal, the part being on a wiring-designed line, based on a route of the line and a physical condition around the route; a route modification processing unit to modify the route of the line by moving the extracted part on the line in the condition where noise contaminates the signal to a position that avoids the condition where noise contaminates the signal; and a line length adjusting unit to conduct a line length adjustment on the line to compensate for a variation of the line length of the line when the variation of the line length of the line occurs due to modifying the route of the line, wherein the route modification processing unit modifies the route of the line so that a part on the line crossing a position that is on a wiring layer and that corresponds to a clearance for isolating a plane pattern and a via provided on an adjacent layer, crosses the position on the wiring layer corresponding to the plane pattern provided on the adjacent layer.