01/01/1993 09:00 AM
Computer Engineering
The flexibility of the rubber-band wire model is very promising for routing and optimizing today\'s complex VLSI and MCM. In this paper we described a practical layer assignment algorithm used with a rubber band router. The algorithm uses a steepest descent approach with an heuristic function which estimate the wiring length of the generated assignment. We formulate the cost function and present an efficient way to compute it. The use of the cost function enable to control the final layout and to achieve balance between wire length and number of vias. The algorithm can be use as well for cost-driven one an a half layer designs in which one wiring layer has only short \"jumpers\" and is embedded in the ground layer.
