SUMMARYA new routing system is described, which can be applied to printed wiring boards of different wiring densities such that the number of wiring tracks permitted between two consecutive pins of an ordinary dual in line package ranges from one to four. This system is distinctive in that a single-row router is combined with a line-search router in such a way that the search for possible wire segments at the stage of the line search router is implemented channel by channel, with all interconnections within each channel completed later by the single-row router.The program operates on an ACOS 77/900 computer, and has been applied to numbers of boards. Some of the implementation results are also shown to reveal how much the described system may attain its potentialities in the practice of layout of high density printed wiring boards.

Recent advances in the technology of microelectronics have changed the design rule for printed wiring boards, allowing the number of wiring tracks between consecutive pins of an ordinary dual in line package (DIP) to be two or more. When the wiring density augments to that extent, conventional routers are confronted with various difficulties. To cope with this situation, the single‐row router which has topological fluidity can be employed in conjunction with the line‐search router. We have already developed a new routing system constructed of a line‐search router combined with a single‐row router and of a maze‐running router. However in each routing process there are many parameters, the combination of whose values have much influence on the wiring performance of the whole system. In this paper we outline this routing system, describe some experimental results in order to determine values of these parameters, and show that the analysis of implemented results suggests high performance for high density printed circuit boards (PWB's).