Common-mode inductors, what magic do they have to make electronic devices run stably?
Publish Time: 2024-09-16
Common-mode inductors play an important role in electronic devices, especially in the field of switching power supplies. Their magic is mainly reflected in the suppression of electromagnetic interference (EMI) and the improvement of power quality, thereby ensuring the stable operation of electronic devices.
1. Suppression of electromagnetic interference (EMI)
Filtering of common-mode interference: Common-mode inductors are mainly used to filter out common-mode interference signals on power lines. These interference signals are external interference introduced by the power supply line or noise generated inside the electronic equipment, which pose a threat to the stability of the power supply and the normal operation of other electronic equipment. Common-mode inductors generate high impedance to common-mode signals through their special winding structure and magnetic core materials, thereby effectively suppressing this interference.
Suppression of series-mode interference: Although the main design goal of common-mode inductors is to filter out common-mode interference, they can also suppress series-mode interference to a certain extent. Series-mode interference is the noise generated between power lines, and the design of common-mode inductors enables them to have a good suppression effect on both types of interference.
2. Improvement of power quality
Stable output voltage: By filtering out interference signals on the power line, common-mode inductors help maintain the stability of differential-mode signals normally transmitted by the power switch chip line. This avoids signal distortion or bit errors caused by electromagnetic interference, thereby improving the output quality of the power supply.
Enhanced equipment compatibility: In today's increasingly complex electromagnetic environment, electromagnetic compatibility between electronic devices is particularly important. The use of common-mode inductors helps devices to avoid external noise interference while meeting electromagnetic compatibility (EMC) requirements, ensuring the normal operation of other electronic devices in the same electromagnetic environment.
3. Design and application considerations
Performance parameter selection: The performance parameters of common-mode inductors, such as inductance, rated current, operating frequency, etc., need to be selected according to the specific application environment and circuit requirements. Suitable common-mode inductors can effectively filter out electromagnetic interference without adversely affecting other parts of the circuit.
Miniaturization and lightweight trends: With the miniaturization and integration trend of electronic equipment, the design and manufacture of common-mode inductors are also facing higher challenges. How to achieve miniaturization and lightweighting of common-mode inductors while ensuring performance is an important direction of current research.
In summary, common-mode inductors, with their unique magic - suppressing electromagnetic interference and improving power quality - provide a strong guarantee for the stable operation of electronic equipment.
