The switching power supply high-frequency transformer is generally shielded for the first time, and is not mentioned above. Switching power supply is a high-frequency product, PCB component layout for EMI, please pay close attention to this point.

If the switching power supply has a mechanical casing, the structure of the casing has a great influence on the radiation. Please pay close attention to this point. There are certain differences in the parameters of the main switch and main diodes, which have certain influence on EMC. Please pay close attention to this point.