Graphic PCB wiring digital, analog, power supply, single point grounding anti-interference!

When we conduct PCB cabling, we always face two or three kinds of situations on one board. The silly practice is of course, regardless of the case of November 21, copper is applied as long as it is the ground. This is not a problem for low-speed boards or boards that are insensitive to interference. Otherwise, the Boards may not work properly. Of course, if there are many places on a board, even if the Board has no requirements, but from a rigorous and serious point of view, we still need to use the method mentioned in this article to wiring, to optimize the entire system and maximize its performance! Of course, I will not talk about some basic concepts of these regions and why they should be separated. If you don't understand them, check them yourself!

Finally, there are also many posts on the Internet about this issue, but most of them are text descriptions and no illustrations, which make people feel that they have always known but do not know why, in this bold illustration, I want to give my thoughts. If not, I hope you can give me some advice and leave a message. Thanks ~

 

1. Digital, analog, and power supply on the Board:

From this figure, we can see that the analog and digital locations are completely separated, and finally each point is connected to the power source, which can prevent the mutual Crosstalk of the ground signal from affecting some sensitive components, as we all know, digital components have a higher Interference tolerance than analog components, while the noise on the digital ground is generally large, so separating them can reduce this effect. In addition, the single point grounding position should be as close as possible to the inlet of the power source (initial position) of the Board, so that the interference can be minimized by the principle that the current is always returned by the shortest short-circuit runoff.

 

2. Only digital and power sources are available on the Board:

From this figure, we can see that only a single point of grounding, such as 0 euro resistance or magnetic beads, can be used between the power source and the digital ground, similarly, the single point grounding position should be as close as possible to the entry of the Board power source location (start position ).

Iii. display the PCB system I have drawn (in the second case ):

1. Ground Partitioning

2. 0 euro resistance Single Point Grounding

3. Front View

Summary: The diagram in this article is very suitable for the PCB ground layout of the single-chip microcomputer control system. Other systems can also be referred!