What Is a Circuit Board Via and Why It Matters in PCB Design A circuit board via is a small plated hole that electrically and thermally connects copper layers in a printed circuit board. At first glance, it looks like a tiny dot or ring on a board, but its role is enormous. Every time a signal must travel from a top-layer component to an inner power plane, or from a buried trace to a surface pad, a via provides the vertical path. Without vias, multilayer PCBs would be limited to simple edge connections and would not support the dense routing, compact form factors, and high-speed performance that modern electronics…