How can the multi-layer board of the intelligent low-voltage monitoring unit improve EMC performance?

Multilayer PCBs improve EMC performance through optimized stack-up design. A recommended 6-layer stack-up is: L1 (signal), L2 (ground), L3 (signal), L4 (power), L5 (ground), and L6 (signal). Key principles: Each signal layer should be adjacent to a ground plane; the power plane should be tightly coupled to the ground plane. High-speed signals should be placed on the inner layer (L3), while low-speed signals and power should be placed on the outer layers. The ground plane should be intact, and the power plane should be appropriately segmented. This stack-up design shortens the signal return path, reduces radiated emissions by 12dB, and improves immunity by 15dB.