Introduction of relevant knowledge about absorbing materials

Absorbing material is a kind of noise reduction magnetic film made of soft magnetic powder and resin and other raw materials in a certain proportion. It has high permeability and soft sides covered with double-sided tape. As long as it is pasted in the right position, it has a good noise suppression effect. Nowadays, electronic products are running faster and faster, and many high-speed circuits often encounter a large number of electromagnetic interference signals. High-speed digital signal circuits, switching circuits, pulse generator circuits, and high-power control circuits change voltage and current rapidly in a very short period of time, or when circuits containing inductors and capacitors are frequently switched on and off.
　　With the rapid change of magnetic field, electric field and electric charge, it is also easy to produce electromagnetic interference. However, with the rapid development of electronic technology, the functions of circuits have become more and more diverse, and the structure has become more and more complex. The working power gradually increases, and the system frequency gradually increases. At the same time, the requirements for sensitivity are getting higher and higher. It is difficult to ensure that the system does not produce some electromagnetic radiation. Filming or external electromagnetic interference.
　　In order to make the system reach EMC, if handled improperly, it will not only affect the performance and quality of the circuit board, but also cause the entire circuit system to fail to work. When these interference problems cannot be solved by design, we can use shielding devices of absorbing materials to suppress EMC and improve EMC. Therefore, in electronic devices with EMI, EMC can be improved. Engineers must know how to use absorbing materials to quickly achieve interference suppression. The absorbing material is usually sheet material, which is usually cut to the appropriate size and shape when used.

1, the product can be installed around the inner wall of the shell, which can reduce the electromagnetic environment of the equipment, so that the components operate in a relatively compatible electromagnetic environment.
　　2, two high-speed chips interfere with each other or a chip radiation interference with adjacent components. Microwave absorbers can be connected between two ics to suppress high-frequency interference.
　　3, the interface of the metal shield is easy to leak electromagnetic radiation, so the product can be attached to the interface to absorb the leaked electromagnetic wave.
　　4, when two PCB substrates are close to each other or stacked together, they are easy to interfere with each other. At this point, the absorbing material needs to be attached to the substrate to directly isolate the interference, which has excellent results.
　　5, in the equipment, electromagnetic radiation is usually transmitted through these wires to other interfered EMS components. We can effectively filter high-frequency radio waves by attaching products to flexible wires, and we can also wrap round wires to suppress high-frequency transmission.
　　6, the radiation of electromagnetic waves will eventually lead to the existence of radiation interference sources, such as clock signal generators, which can only be attenuated by adhering to absorbing materials on the interference source. In short, the occurrence of interference is always composed of interference sources, conductive interference paths and interference sensitive components. Thus, by applying a wave-absorbing material, only one of these three elements can be inhibited. An EMC implementation occurred.