How to avoid ground loops in hybrid grounding of power DTU?

To avoid mixed grounding loops in the DTU, a reasonable combination of single-point and multi-point grounding is necessary. Low-frequency circuits (<1MHz), such as power ground and chassis ground, should use single-point grounding, with all ground wires converging at the power input. High-frequency circuits (>1MHz), such as digital and RF circuits, should use multi-point grounding, directly connected to the ground plane via vias. Single-point and multi-point grounding should be connected via a PBZ1608A-102Z0T ferrite bead or an RC network (10Ω + 100nF). During layout, sensitive circuits should be kept away from grounding connection points. Use isolation devices (such as ADuM1410) to break signal ground loops. Analyze ground loop currents through simulation; the optimized current should be less than 10mA. Mixed grounding can effectively suppress ground loop interference.