Are there any requirements for openings on the FR shield? Generally speaking, what is the minimum diameter? If the hole gets bigger, what will be the impact? Today, Ningbo Hexin engineers will answer
First of all, according to the principle of the shielding cover, whether it needs to be fully enclosed or semi-enclosed is still very much related to the components used. When the components in the shielding cover are working, they will generate heat energy. If the heat energy is not dissipated in time and there is no heat dissipation hole, it is easy to cause the shielding cover to burst.
Perforating the FR shield is to consider the effectiveness of the shielding effect on the one hand, and on the other hand to consider the heat dissipation. Considering that the reflection loss is greater than 20dB, the maximum aperture on the FR shield should not exceed 1/20 of the wavelength of the signal to be shielded.
The maximum diameter of the opening at the top of the FR shield shall not exceed 2.5 mm, and the opening diameter is generally 1.5 mm. If there is an RF microstrip line from the shielding layer through the surface layer, this hole must be opened. The opening is rectangular, the width is equal to the distance between the two ends of the radio frequency microstrip line, not more than 2.5 mm, and the height is not less than 1 mm. Other low frequency traces must not have holes.