Design Rule Check (DRC)
What Is a Design Rule Check (DRC)?
A Design Rule Check (DRC) is an automated verification step in the PCB design workflow that validates a completed layout against a defined set of manufacturing and electrical constraints. DRC checks for issues such as minimum trace width and spacing violations, insufficient annular ring size, drill-to-copper clearances, unconnected nets, short circuits, and silk screen overlaps. Running DRC before sending a board to fabrication is essential for catching errors that could result in manufacturing defects, costly respins, or non-functional hardware.
Most EDA (Electronic Design Automation) tools — including Altium Designer, Cadence Allegro, and KiCad — include built-in DRC engines. Engineers define their design rules based on the target fabrication house's capabilities, and the DRC engine flags any violations for manual review and correction. While DRC is a powerful safety net, it is inherently reactive: it identifies problems after they've been introduced into the layout.
Moving Beyond Post-Layout DRC With Physics-Driven Generation
The fundamental limitation of traditional DRC is that it runs after the layout is already complete. Fixing violations at this stage often triggers a cascade of additional changes, as modifying one trace can create new clearance issues or impedance problems elsewhere. Physics-driven layout engines address this by enforcing design rules and physical constraints during the generation process itself. Every placement decision and routing path is evaluated against the full constraint set in real time, producing layouts that pass DRC on the first review and dramatically reducing the time spent on post-layout cleanup.
