The absorbing material is a kind of noise-reducing magnetic film made of soft magnetic powder and resin in a certain proportion. It has high permeability and soft side covering double-sided tape. As long as it is pasted in the correct position, it has an excellent noise suppression effect. Nowadays, the operation speed of electronic products is getting 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 rapidly in voltage and current in a short period of time, or when circuits containing inductors and capacitors are frequently turned on and off.
With the rapid change of electric field, electric field, and electric charge, electromagnetic interference is also prone to occur. However, with the rapid development of electronic technology, the functions of the circuit have become more and more diversified, 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 generate some electromagnetic radiation. Take pictures or receive external electromagnetic interference.
In order to make the system reach EMC, improper handling 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 equipment with EMI, EMC can be improved. Engineers must know how to use absorbing materials to quickly achieve the effect of interference suppression. The absorbing material is usually a sheet, which is usually cut into a suitable 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 device and make the components operate in a relatively compatible electromagnetic environment.
2. Two high-speed chips interfere with each other or the radiation of one chip interferes with adjacent components. The microwave absorber 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 leakage electromagnetic wave.
4. When two PCB substrates are close to or superimposed on each other, they are easy to interfere with each other. At this time, the absorbing material needs to be attached to the substrate to directly isolate the interference, which has an excellent effect.
5. In the equipment, electromagnetic radiation is usually transmitted to other interfered EMS components through these wires. We can effectively filter high-frequency radio waves by pasting the product on a flexible cord, and we can also wind 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 absorbing materials on the interference sources. In short, the occurrence of interference is always composed of interference sources, conducted interference paths and interference-sensitive components. Therefore, by applying a wave absorbing material, only one of these three elements can be suppressed. The implementation of EMC occurs.