Shragowitz In this research fuzzy logic is being applied to reasoning about problems of VLSI physical design and printed circuit boards (PCB). This includes identification of important factors for each problem, selection of linguistic variables, formulation of the membership functions for linguistic values in fuzzy sets and formulation of the decision rules. A fuzzy logic model of timing-driven placement, where area, timing, and routability may become conflicting goals is being developed. This model incorporates timing analysis and prediction, especially pre- layout prediction of path and net criticality, and weight functions for nets in computation of timing bounds. A second fuzzy logic model for placement of cells on a VLSI chip in the presence of conflicting goals is being developed. The model is being adapted to PCB placement, taking into account parameters such as connectivity, timing, transmission line effects, routability, and thermal impact. Experiments with the algorithms on benchmark circuits are being performed.
