CONVERGE: a circular-assignment-based switchbox router with via reduction

The authors propose a new circular assignment-based switchbox router, CONVERGE, based on segment assignment in circular routing. The CONVERGE router is divided into three phases: the iterative phase, the merging phase and the via reduction phase. In the iterative phase, circular routing will be applied to assign vertical or horizontal segments cycle by cycle. In the merging phase, if switchbox routing is successful, the routing result can be further improved by merging adjacent segments of the same routing net. Finally, in the via reduction phase, constrained layer assignment can further reduce the number of vias. As a result, many benchmarks have been tested on the switchbox router, and these benchmarks are successfully routed. In addition, the proposed switchbox router has better routing results than other switchbox routers on vias and wire length.