Computer motherboard shielding cover, what are the precautions for designing shielding cover + 3.0 precision design system

The manufacturer of shielding covers for computer motherboards said that there are a few points for attention when designing shielding covers. Xiaoshuo has compiled some relevant information for you. Let's take everyone to understand it together, so that you will no longer have to worry about designing shielding covers. (1) When the frequency of the interfering electromagnetic field is high, the eddy current generated in the low-resistivity metal material is used to form the cancellation effect of the external electromagnetic wave, thereby achieving the shielding effect. (2) When the frequency of interfering electromagnetic waves is low, materials with high magnetic permeability should be used, so that the lines of magnetic force are limited to the inside of the shield and prevent spreading to the shielded space. (3) In some cases, if a good shielding effect is required for both high-frequency and low-frequency electromagnetic fields, different metal materials are often used to form a multi-layer shielding body. If the shielding cover or gasket is made of plastic coated with a conductive layer, adding an EMI gasket will not cause too many problems, but the designer needs to consider that many gaskets will wear on the conductive surface, usually metal gaskets The surface of the coating is more prone to wear. Over time, this wear will reduce the shielding efficiency of the gasket joints and cause problems for subsequent manufacturers. If the shielding cover or the gasket structure is metal, a gasket can be added to cover the surface of the gasket before spraying the polishing material, and only conductive film and tape can be used. If tape is used on both sides of the joint gasket, mechanical fasteners can be used to fasten the EMI gasket, such as a 'C-type' gasket with plastic rivets or pressure sensitive adhesive (PSA). The gasket is installed on one side of the gasket to complete the EMI shielding. Hardware, 15 years of focusing on computer motherboard shielding, 20,000+ sets of customized stamping die production experience, monthly processing capacity of 100+ sets of molds, hundreds of precision processing production equipment, daily production capacity of 3 million punches, and silk-like stamping accuracy up to 0.01 mm, the raw materials are imported and the original national standard factory, and 16 quality inspections are strictly controlled.