Basic Wiring Rules
We have explained many times about how to design PCBs, but we talk little about wiring rules. In this article, EPCB lists several basic wiring rules for your reference.
a. The power line and ground should be as radial, and a signal line may not appear loopback trace.
b. Some of the key signal line can be pre-wired at the same time on both sides of the line as far as possible vertical signal lines, parallel prone to parasitic coupling.
c. Generally, normal via is not less than 30mil.
d. Add protection is the way to avoid the short of signal lines.
e. A painting fixed wiring area from the PCB edge should less than 1mm distance.
f. Generally the sequence of width is that ground> power cables> signal line. Power line width is often not less than 18mil; signal width not less than 12mil; line spacing not less than 10mil.
g. The incoming signal to the printed circuit board plus filtering from high noise to signal area should increase the filtering while using strings way terminating resistor to reduce signal reflection.