Development of an EMC-Constraint PCB Design, Placement and Routing Support Tool

The EMC-constraint CAD layout support tool was developed for the printed circuit board design. In the developed system two possible constraints; signal reflection and crosstalk, were considered. The former was taken into account in the element placement stage and the latter was considered in the routing stage. At the placement stage reflections were first calculated for all combinations of the parameters. And then the allowable length table was constructed. The constraint to the line length and thus the placement was indicated to the designer in the manual layout stage. The crosstalk was also calculated for all possible combinations of the parameters. These results were stored in the database. The routing constraint are given from the database-table during the manual layout operation. The tool can help the layout designer interactively and visually. In this paper the system configuration of the support tool and its applications are demonstrated. The consideration on the other noise sources are now in progress.