What Is A Common Mode Choke？

The common mode choke is an inductive device used to suppress the common mode interference of the circuit.Common mode interference refers to interference signals that affect both signal leads (positive and negative) in a circuit at the same time, usually the injection of external electromagnetic interference signals.

 

 

The selection of common mode choke needs to consider the following factors:

1. Frequency range: The frequency response of the common mode choke needs to cover the frequency range of the interference signal to be suppressed.

2. Rated current: The rated current of the common mode choke should be greater than the maximum common mode interference current in practical application.

3. Inductance value: select according to the inductance value of the common mode choke in the linear region, and generally should meet the requirements of suppressing common mode interference.

When selecting a common-mode choke in a switching circuit, the following factors also need to be considered:

1. Frequency range: The frequency range of the common mode choke needs to cover the switching frequency range.

2. DC resistance: The DC resistance of the common mode choke needs to be as small as possible to avoid excessive power dissipation.

3. Size: The smaller the size, the better to meet the size requirements of modern electronic equipment.

4. High-frequency performance: The self-resonant frequency of the common-mode choke needs to be high enough to avoid unnecessary oscillation in the high-frequency switching circuit.

In short, the selection of common mode choke needs to comprehensively consider factors such as frequency range, rated current, inductance value, inductor size, and high-frequency performance to meet the requirements of specific applications.