Modern Automatic PCB Placement with Complex Constraints

Modern printed circuit board (PCB) placement involves increasingly complex constraints, including diverse wire widths, irregular component geometries, stringent clearance rules, and intricate power and signal flow requirements. Manual placement under such conditions is time-consuming and error-prone. This paper presents a constraint-aware placement framework that integrates three key techniques: (1) a simulated annealing-based pad alignment method to reduce wire crossings and preserve spacing compliance, (2) a force-directed global placement guided by anchor points extracted from power circuit flows, and (3) a window-based legalization algorithm that ensures overlap removal and rule adherence. Experimental results on real industrial designs demonstrate that our method improves routability by 13.5% and reduces runtime by 26% compared to ePlace-MS. Moreover, our approach outperforms the recent GPU-accelerated PCB placer, Cypress, by over 50% in routability, while delivering complete full-board layouts under practical constraints.