Talking about the electromagnetic interference problem of ACDC power module
2022-08-16

How to suppress electromagnetic radiation has always been a difficult problem that cannot be ignored in the design of switching module power supplies. It is not only related to the safety of the power supply module itself, but also involves the safety factor and reliability data system of the entire system. All-round suppression of the noise interference of the switching module power supply will make the switching power supply module more widely used.


The first is the concept of electromagnetic interference


Electromagnetic radiation (Electromagnetic Interference, EMI) refers to all the magnetic induction conditions caused when the conduction or electromagnetic field reduces the characteristics of the device, equipment or system with voltage and current, or will cause adverse effects on living organisms or substances.


On the other hand, the generation of electromagnetic interference


1, produce electromagnetic interference


ACDC power module


The origin of scrambling, sensitive facilities and decoupling paths, are called the basic elements of electromagnetic interference. For switching module power supplies, drastic changes in current or voltage can cause noise, so high-power and high-frequency electronic components are a source of EMI noise. Specifically, its origins are:


(1) External coupling and interference (mainly generated at the input and output);


(2) switch;


(3) Transformer;


(4) Diode


(5) Energy storage inductance;


(6) Unreasonable PCB layout and wiring cause loop interference.