How does equipotential bonding in power DTUs suppress common mode?

Suppressing DTU common-mode interference through equipotential bonding requires equalizing the potentials of all metal components within the system. Connect all metal casings, shielding layers, and grounding conductors to the same grounding reference point using low-impedance wires (cross-sectional area ≥ 4 mm²). The connecting wire length should be less than 20 cm to avoid inductive effects. Connect a high-frequency capacitor (100 nF) in parallel at the connection point or install a ferrite core to provide a high-frequency noise path. On the PCB, all functional grounds should be connected at multiple points to form a unified ground plane. After equipotential bonding, the common-mode voltage difference should be less than 0.5 V. Testing shows that the system's EFT immunity can be improved from ±2 kV to ±4 kV, and common-mode noise suppression is improved by 25 dB.