Electrostatics-Based Analytical Global Placement for Timing Optimization

Placement is a critical stage for VLSI timing closure. A global placer without considering timing delay might lead to inferior solutions with timing violations. This paper proposes an electrostatics-based timing optimization method for VLSI global placement. Simulating the optimal buffering behavior, we first present an analytical delay model to calculate each connection delay accurately. Then, a timing-driven block distribution scheme is developed to optimize the critical path delay while considering the path-sharing effect. Finally, we develop a timing-aware precondition technique to speed up placement convergence without degrading timing quality. Experimental results on industrial benchmark suites show that our timing-driven placement algorithm outperforms a leading commercial tool by 6.7% worst negative slack (WNS) and 21.6% total negative slack (TNS).