Automatic design method for semiconductor device

An automatic design method for automatically positioning external terminals of a semiconductor device, said external terminals being provided on a semiconductor chip having pads and having peripheral sides, said automatic design method comprising the steps of:

• determining positioning sections of said external terminals by provisionally determining positions of said external terminals, dividing a positioning region into a plurality of said positioning sections, and assigning at least one side to each positioning section based on a positional relationship between said sides and said positioning sections;
• determining allocated sides by allocating said external terminals in each positioning section to a corresponding side to which said positioning section is assigned or to one of corresponding sides if a plurality of corresponding sides are assigned to said positioning section, until the number of said external terminals allocated to said sides reaches the number of said pads arranged along said sides;
• determining positioning columns by grouping said external terminals allocated to each side into groups arranged in a direction perpendicular to said side to which said external terminals are allocated, and grouping said pads arranged along each side into groups according to the number of said external terminals of corresponding groups, starting from an endmost pad arranged along each side;
• determining positioning rows by assigning said external terminals of said groups to said pads of corresponding groups;
• and
• editing positions of said external terminals by connecting said external terminals and said pads assigned to each other by means of linear virtual wirings, checking whether said virtual wirings cross each other, and replacing correspondences between said external terminals and said pads of crossing virtual wirings with each other if there are crossing virtual wirings.