In a double-sided PCB, how can the installation position of common-mode inductance be optimized to avoid ground interference? ​

In a double-sided PCB, the installation position of the common-mode inductor needs to be determined in the following ways to avoid ground interference near the interface terminal: Try to install the common-mode inductor near the power/signal input interface (such as DC socket, connector) so that the interference can be suppressed before entering the system, reducing the path for interference to spread through the ground plane.

Avoid dividing the ground plane at the inductor: Avoid bridging the inductor across the divided area of the PCB ground plane (such as the junction between analog ground and digital ground) to prevent ground current from coupling through the inductor core to form interference.

Hollow out the ground plane below the inductor: Remove the ground copper layer in the PCB area below the inductor to reduce the parasitic capacitance between the ground plane and the inductor winding, avoiding high-frequency interference coupling to the ground plane through capacitance.

Separate the input and output ground planes of the inductor: Separate the inductor input ground plane from the output ground plane through an isolation strip, with only Y capacitors or single-point grounding connections.