The core goal of PCB routing is not simply "connecting the wires," but rather, while fulfilling electrical functional requirements, ensuring cleaner signals, less interference, and more stable production. The first step is usually "planning before routing," meaning functional zoning should be done before actual routing begins, such as separating power, digital, analog, and high-speed signal areas. Once component placement is reasonable, subsequent routing becomes much easier. In particular, decoupling capacitors around the main control chip should be placed as close as possible to power pins; otherwise, even the best routing will be hampered by power supply noise.
In actual routing, priority is crucial, generally following the order of "power first, then critical signals, and finally general signals." Power lines should be as wide as possible, and ground lines should be as complete as possible, avoiding breaks or detours, as the ground line itself is the return path for all signals. High-speed signals should take the shortest possible path, reducing the number of vias, as each via introduces additional parasitic inductance and capacitance, affecting signal quality. Avoid 90° right angles when routing; instead, use 45° bends or rounded transitions to reduce signal reflection and sharp-point radiation-a fundamental practice in high-speed design. Another easily overlooked technique is "interference control." For example, clock signals and RF signals should be kept away from high-current circuits and switching power supply areas, otherwise they are easily contaminated by noise. Differential signals must be kept of equal length, equidistant, and tightly coupled, otherwise their anti-interference characteristics will be compromised. If necessary, a full-area ground plane can be used for shielding to improve electromagnetic compatibility. Finally, in the final stage of wiring, try to avoid thin "antenna lines," isolated copper traces, and overly dense routing, while leaving space for test points and maintenance. These details directly affect product yield and future maintainability.
