On circuit clustering for area/delay tradeoff under capacity and pin constraints

In this paper, we propose an iterative area/delay tradeoff algorithm to solve the circuit clustering problem under the capacity constraint. It first finds an initial delay-considered area-optimized clustering solution by a delay-oriented depth-first-search procedure. Then, an iterative procedure consisting of several reclustering techniques is applied to gradually trade the area for the performance. We then show that this algorithm can be easily extended to solve the clustering problem subject to both capacity and pin constraints. Experimental results show that our algorithm can provide a complete set of clustering solutions from the area-optimized one to the delay-optimized one for a given circuit. Furthermore, comparing to the existing delay-optimized algorithms, ours achieves almost the same performance but with much less area overhead. Therefore, this algorithm is very useful on solving the timing-driven circuit clustering problem.