Patent ID: 7080343

Claim:
An apparatus for selecting an optimum printed circuit board based on an intended use of the printed circuit board, said apparatus comprising: board information storing means for storing information about a plurality of printed circuit boards; component information storing means for storing information about components to be mounted on said plurality of printed circuit boards wherein said component information differs based on the intended use of the printed circuit board; pin number calculating means for deriving a total number of signal pins, a total number of power supply pins and a total number of non-connected pins based on a total number of pins of said components to be mounted on said optimum printed circuit board stored by said component information storing means, comprising deriving a ratio of a number of signal pins to said total number of pins, a ratio of a number of power supply pins to said total number of pins, and a ratio of a number of non-connected pins to said total number of pins, which are stored by said component information storing means; between-signal connection number calculating means for deriving a total number of connections between signal pins based on said total number of signal pins, which includes a first function stored by said component information storing means; power supply connection number calculating means for deriving a total number of connections relative to a power supply layer of said optimum printed circuit board based on said total number of power supply pins, wherein said power supply connection number calculating means comprises: means for deriving a total number of ground connections using said total number of said power supply pins derived by said pin number calculating means, and a second function that is stored by said component information storing means means for deriving a total number of power supply connections using said total number of the power supply pins derived by said pin number calculating means, and a third function that is stored by said component information storing means; and means for deriving said total number of connections relative to said power supply layer of said optimum printed circuit board based on said total number of ground connections and said total number of the power supply connections; minimum total wiring length calculating means for deriving a minimum total wiring length in said optimum printed circuit board based on said total number of connections between said signal pins and said board information; maximum total wiring length calculating means for deriving a maximum total wiring length in said optimum printed circuit board based on said total number of connections between said signal pins, said total number of connections relative to said power supply layer and said board information; and index calculating means for deriving an index representing a ratio of said maximum total wiring length to said minimum total wiring length.