LAYOUT PARAMETER EXTRACTION DEVICE

PROBLEM TO BE SOLVED: To increase the precision of circuit simulation by handling a wiring part as a distribution constant line circuit which considers the equivalent resistance of a driving circuit connected to the wiring part and the load capacity of an adjacent element and substituting a proper line circuit for it. SOLUTION: A line table 150 is used to substitute a specific line circuit for the wiring part so that circuit simulation can be performed almost in the actual state when the circuit simulation is performed, and considers the equivalent resistance Rt of the driving circuit of the wiring part and the load capacity Ct of the element following the wiring part. Then an approximate circuit selection part 130 selects the proper line circuit as the wiring part according to the ratio Rt/R of the resistance Rt of the driving circuit and wiring resistance R and the ratio Ct/C of the load capacity Ct and wiring capacity C. Further, a parameter extraction part 140 extracts parameters needed for the circuit simulation from all circuits having wiring parts replaced with proper line circuits by the approximate circuit selection part 130.