What is the relationship between the Curie temperature of the magnetic core and the maximum operating temperature of the common mode inductor? ​

The Curie temperature of the magnetic core and the maximum operating temperature of the common mode inductor are in a relationship of constraint and being constrained. The Curie temperature is the critical temperature at which the magnetic core loses its ferromagnetism (with a sharp drop in permeability). If the operating temperature of the common mode inductor exceeds the Curie temperature, the permeability of the magnetic core approaches 1, and the inductance drops significantly (possibly to less than 1% of the original value). The common mode impedance decreases sharply, completely losing its ability to suppress common mode interference. Therefore, the maximum operating temperature of the common mode inductor must be lower than the Curie temperature of the magnetic core, with a safety margin (usually 20-50°C lower) to avoid temperature exceeding limits due to environmental temperature fluctuations or self-heating due to losses. For example, the Curie temperature of a ferrite magnetic core is approximately 200-400°C, and its maximum operating temperature for inductance is usually limited to 125-150°C.