Multilayer circuit boards are starting to pop up, which is composed of a connecting wire and a bonding pad. It can conduct a multilayer circuit and ensure the insulation between each other. Multilayer PCB is mainly used to reduce costs and excessive interference. So we should pay more attention to the layout and wiring of the multilayer circuit board.
There are several general rules in wiring:
1. The setting principle of the distance between the printed wiring of the components
The spacing constraints between different networks are caused by electrical insulation, manufacturing processes, and components. If the potential difference between the two components or the network is large, the problem of electrical insulation should be considered. We should pay attention to the adequate safety spacing if PCB is powered by high voltage and low voltage.
2. The choice of the form of the line on the corner of the line
We should set the corner line mode to ensure that the board is easy to manufacture and maintain beautiful. The connection between the wire and the pad should be smooth as far as possible and the emergence of little tip need to be avoided.
3. The determination method of printing trace width
The line width is determined by the current level of the wire and the interference factor, the larger the current, the wider the line width. Meanwhile wide wire can reduce the impedance of the line and improve the performance of anti-interference.
4.Anti interference and electromagnetic shielding of printing
The interference of the lead wire is mainly introduced by the interference between the wire and the crosstalk between the signal lines.
In the actual operation, wiring is a very flexible thing, so the above principles can only be used as a reference in design.