In the process of designing PCB boards, seemingly simple holes, without leaving a sound is likely to bring great negative effects to the board. Today, let’s tell you how to reduce the adverse effects of

the parasitic effect of the hole in the design of the PCB circuit board:

1. The pins of the power supply and the ground should be punched in the nearest hole, and the shorter the lead between the hole and the pin, the better, because they will lead to an increase in

inductance. At the same time, the power and ground leads should be as thick as possible to reduce impedance.

2. the signal wiring on the PCB board should not be changed as far as possible, that is to say, try not to use unnecessary holes.

3. the use of a thinner PCB board is conducive to reducing the two parasitic parameters of the hole.

4. from the perspective of cost and signal quality, choose a reasonable size of the hole size. For example, for the design of 6-10 layers of memory module PCB circuit boards, it is better to choose

10/20Mil(drill/pad) holes, and for some high-density small-size boards, you can also try to use 8/18Mil holes. Under current technical conditions, it is difficult to use a smaller size of the hole. For

the power supply or ground wire hole, you can consider using a larger size to reduce the impedance.

5. Place some grounded holes near the holes of the signal change layer to provide the nearest loop for the signal. You can even place a large number of excess ground holes on the PCB board. Of

course, you need to be flexible in your design.

The through hole model discussed earlier is the case that each layer has a pad, and sometimes, we can reduce or even remove the pad for some layers. Especially in the case of very large hole density,

it may lead to the formation of a fault slot in the copper layer. To solve this problem, in addition to moving the position of the hole, we can also consider reducing the size of the pad in the copper

layer.