How should the power ground and signal ground of an intelligent low-voltage monitoring unit be separated?

Power ground and signal ground are separated to prevent high-current noise interference. A single-point connection method is adopted after grounding. Power ground is used for power conversion; signal ground is used for sampling and communication. The two are connected at a single point near the DC-DC output terminal by a ferrite bead PBZ1608A-102Z0T (1000Ω@100MHz). PCB design: Power ground has complete copper plating with trace width meeting current requirements; signal ground uses a grid-like copper plating. Digital ground and analog ground are separated by ferrite beads. The chassis ground is connected to earth ground separately. This design can reduce ground noise by more than 18dB, meeting the IEC 61000-4-8 power frequency magnetic field immunity test requirements.