A neural network approach for multilayer over-the-cell channel routing problems

A new algorithm for multilayer over-the-cell channel routing problems using two neural networks is presented in this paper. In the multilayer over- the-cell channel routing problem, signal nets may be placed not only in the multilayer channel between two cells, but also on the multilayer routing area over the cells. The goal of our algorithm is to route all the given nets in both routing areas with the minimum number of tracks in the channel. Our algorithm consists of four steps: (1) extracting nets for the over-the-cell routing, (2) routing nets in the multilayer over-the-cell muting area by the neural network, (3) transforming nets for the channel routing and (4) routing nets in the multilayer channel by the neural network. The performance of our algorithm was verified through seven benchmark problems with 1-4 layers for the over-the-cell and 2-8 layers for the channel. The simulation results support the flexibility of our algorithm in the multilayer over-the-cell channel routing problem.