MegaRoute: Universal Automated Large-Scale PCB Routing Method with Adaptive Step-Size Search

The automation of very large-scale PCB routing has long been an unresolved problem within the industry due to the variant electronic components and complex design rules. Existing automated PCB routing methods are primarily designed for single component (e.g., BGA, BTB, etc.) or for simple and small-scale PCBs, and often fail to meet the industry requirements for large-scale PCBs. The biggest challenge is to ensure nearly 100% routability and DRC compliance while achieving high efficiency for large-scale PCBs with various components. To address this challenge, we propose MegaRoute, a precise, efficient, and universal PCB routing method that surpasses the routing routability and DRC compliance of existing methods, including commercial tools, for PCBs with thousands of nets. MegaRoute introduces an adaptive step-size search algorithm that adjusts exploration steps based on design rules and surrounding obstacles, improving both routability and efficiency. We incorporate shape-based obstacle detection for strict DRC compliance and use routing optimization techniques to enhance routability. We conduct extensive experiments on hundreds of real-world PCBs, including mainboard PCBs with thousands of nets. The results show that MegaRoute achieves over 98% routability across all PCBs with DRC-free results, significantly outperforming the state-of-the-art methods and mainstream commercial tools.