Why You Should Stop Using Auto-Routers and How to Route Manually

Automated routing produces functional layouts but generally overlooks significant design parameters, including impedances, return paths, and EMI; consequently, inefficient routing (due to the need for excessive vias) and poor signal integrity (especially where high-speed designs are concerned) will occur. Alternatively, manual routing allows complete design control over critical nets through short trace lengths, direct trace paths, and solid reference planes. Subsequently, the power and high current traces should be routed first, the sensitive signals second, and all other (lower priority) nets should be routed last. It is best to route with the same trace width and spacing using design rules as a guide. While utilizing automated routers can save time upfront, the end result from manually routing will be cleaner and make for more reliable and production-ready PCBs.