PCB high-speed board more than 4 layers of wiring experience:
1,3 points above the connection, as far as possible in turn through the points, easy to test, line length as short as possible.
2, try not to pin between pins, especially between the IC pins and around.
3, between the different layers of the line as far as possible not to parallel, so as to avoid the formation of the actual capacitance.
4, wiring as far as possible is a straight line, or 45 degrees fold line, to avoid electromagnetic radiation.
5, ground, power cord at least 10-15mil above (for logic).
6, try to let the polyline line together, increase the ground area. Between lines and lines as neat as possible.
7, pay attention to the components discharged evenly for installation, plug-in, welding operation. Text discharge in the current character layer, the location is reasonable, pay attention to the direction, to avoid being blocked, easy to produce.
8, component emissions to consider the structure, the chip components should be positive and negative in the package and the final mark, to avoid space conflict.
9, the current printed circuit board can be 4-5mil wiring, but usually 6mil line width, 8mil line distance, 12 / 20mil pad. Wiring should be considered into the impact of current and so on.
10, the function block components as far as possible together, the zebra and other components near the LCD can not rely on too close.
11, through the hole to be coated with green oil (set to negative times).
12, the battery seat is best not to place the pad, over the air, etc., PAD and VIL size reasonable.
13, after the completion of wiring to carefully check each line (including NETLABLE) is really connected (available lit method).
14, the oscillation circuit components as far as possible * IC, oscillation circuit as far as possible away from the antenna and other vulnerable areas. Under the crystal to put the ground pad.
15, and more to consider strengthening, digging and unloading components and other means to avoid too much radiation source.