In PCB design, wiring is an important step to complete product design. It can be said that the previous preparation work is done for it. In the entire PCB, the design process of wiring is the most limited, the skills are the smallest, and the workload is the largest. PCB Wiring includes single-sided wiring, double-sided wiring and multi-layer wiring. There are also two ways of routing: automatic routing and interactive routing. Before automatic routing, you can use interactive pre-routing for the lines with stricter requirements. The edges of the input end and the output end should be avoided to be adjacent and parallel to avoid reflection interference. If necessary, ground wire isolation should be added, and the wiring of two adjacent layers should be perpendicular to each other, and parasitic coupling will easily occur in parallel.