Meizhou Hongzhan Electronic Technology Co., Ltd. thinks that there are several reasons for laying copper in general:

1, EMC. For a large area of ground or power supply copper, will play a shielding role, some special, such as PGND play a protective role.

2, PCB process requirements. Generally in order to ensure the plating effect, or the laminate is not deformed, the PCB layer with less wiring is laid copper.

3, signal integrity requirements, a complete return path for high-frequency digital signals, and reduce the wiring of the DC network. Of course, there is heat, special device installation requires copper plating and other reasons.