How does the common mode inductance in a fast-charging charger handle interference suppression from high-frequency switching (>1MHz)? ​

Magnetic core material: Nanocrystalline (such as Hitachi Finemet) or Sendust magnetic cores are preferred, maintaining high magnetic permeability (μi≥1000) and low loss (such as Pcv≤500mW/cm³ at 1MHz/200mT) in frequency bands above 1MHz.

Winding design:

Double-wire parallel winding: 0.3mm×2 strands of enameled wire are used for parallel winding to reduce uneven current distribution caused by proximity effects and enhance high-frequency impedance.

Segmented winding: The winding is divided into 4 segments, with insulating layers inserted between each segment to reduce interlayer parasitic capacitance to below 5pF.

Auxiliary circuit: TVS diodes (such as SMBJ15A) are connected in parallel across the inductor to clamp high-frequency switching spikes (such as 1MHz/100V spikes) and protect the backend circuit.