Magnetic field shielding refers to the use of materials with high magnetic permeability, which can bypass the interfering magnetic flux and avoid interference from being connected to the protected circuit. Moreover, the alternating interference magnetic flux will form eddy currents within the conductive shielding layer, and the eddy current effect will weaken the strength of the external magnetic field. The shielding layer made of materials such as iron and bimo alloy has both functions, which can make the interfering magnetic field lose its influence on the circuit. The weak current signal circuit near the power transformer should avoid magnetic field interference and can be covered with iron and beryllium molybdenum alloy plates. In electronic devices, some components need to prevent interference from external magnetic fields. To solve this problem, it is necessary to use ferromagnetic materials to make a cover, which covers the parts that need to be tampered with inside to isolate them from the external magnetic field. It is also possible to cover the parts that radiate and interfere with the magnetic field, so that they cannot interfere with other parts. This method is called magnetic shielding. Due to the low magnetic resistance of the iron shielding shell, it provides a smooth magnetic circuit for external interference with the magnetic field, allowing the magnetic field lines to short-circuit through the iron shell and no longer affect the components being shielded inside