How can the protection of the power ports of a power DTU take into account EMC?

Balancing DTU power port protection and EMC requirements necessitates the integration of surge protection and filtering functions. Protection components include a 2R600L-8×6 (20kA) gas discharge tube and a 14D511K (6.5kA) varistor for surge absorption. EMC components include a CML4532A-510T common-mode inductor and safety-compliant X/Y capacitors for filtering. The port utilizes a shielded enclosure with conductive pads installed in the gaps. On the PCB layout, the protection components are positioned close to the interface, followed by the filter. The design passes surge testing (IEC61000-4-5, ±4kV) and conducted emission testing (EN55032 Class B). This balanced design ensures port safety and EMC compliance, enhancing reliability.