With the birth of various intelligent electrical appliances, DC-DC power supply module also plays an important role. Many intelligent products need power supply module for data analysis and so on. What is the role of EMC design of DC-DC power supply module? Let's learn about it today.
Shielding and grounding
Shielding can effectively suppress the electromagnetic interference propagating through space. Shielding has two purposes: one is to limit the internal radiation of electromagnetic energy through a region; The other is to prevent external radiation from entering a certain area. Shielding is one of the methods to solve the EMC problem of DC-DC power supply module. The purpose is to cut off the propagation path of electromagnetic wave, mainly to seal the shell of DC-DC power supply module. The key point of grounding is that the potential is the same, the internal circuits do not interfere with each other, and the external interference is resisted. The impedance caused by conductor inductance is minimized, the impedance of grounding circuit is increased, and the interference of grounding circuit is reduced.
Soft switching technology
Using soft switching technology to realize zero voltage switching and zero current switching can greatly reduce the di / dt and DV / dt of power devices. That is, the power transistor can be closed at zero voltage and zero current. If the fast diode is also soft off, the EMI level of DC-DC converter can be greatly reduced.
Optimizing buffer circuit
The buffer circuit with switch driver can also effectively reduce di / dt and DV / dt in the circuit, so as to reduce EMI interference sources. The buffer circuit delays the turn-on and turn off process of the power switching device, thus reducing the EMI level of the DC-DC converter. For the same type of switches, except for the different driving buffer circuit, other conditions are the same, which are determined by experiments.
