Layout 3 W Principle 20 H Principle 5 principles

 

 

3 W principle:

Here, the distance between the line and the line is 3 times the line width. You can do the same for 3 h. But Here H refersLine width. It is not media thickness. To reduce the number of cablesCrosstalkEnsure that the line spacing is large enough. If the center distance of the line is not less than three times the line width, the line can be kept between 70%.The electric field does not interfere with each other.It is called a rule. 98% rules can be used if the electric field reaches without mutual interference. For Emi

 

20 h principle:

It refers to the 20 h distance between the power supply layer and the formation,This is also to suppress the edge radiation effect.. Electromagnetic interference is emitted at the edge of the plate. The power supply layer is reduced so that the electric field is transmitted only within the connected strata. Effectively improves EMC. If the contraction is 20 h, 70% of the electric field can be restricted to the edge of the ground. If the contraction is 98% H, of the electric field can be restricted. For EMC

Five-five rules:

Print board layers selection rules, that is, the clock frequency5 MHz or pulse rising time less than 5ns, Then the PCB must adopt multi-board. This is a general rule. Sometimes, due to cost and other factors, when the dual-board structure is used, it is best to make one side of the printed board as a completeGround plane Layer.

 

 

 

 

 

The clock frequency of the "Five-five rule" is5 MHz or pulse rising time less than 5ns, I seriously do not understand here...