On a pcb circuit board, when components are mounted, various pads will be soldered on it. In fact, the pad is a contact point. In fact, the pcb circuit board is covered with copper. After corrosion, the circuit is left and then on the circuit. For punching, to make the component and the circuit board contact well, the amount of copper on the contact point will generally be more, and the pads are mostly disc-shaped, of course, there are other shapes. Because each electronic product has a different structure, the circuit board pads of each electronic product are different, but they are all based on the principle of as few as possible. The following briefly introduces two special pads.

　　 plum blossom pad;

1. When installing the GND network, the fixed mounting hole will choose the plum blossom pad, because the PCB copper is generally used to pave the copper for the GND network. After installing the PCB shell device in the plum blossom hole, it actually connects the GND to the earth. On occasion, the pcb shell plays a shielding role.

　　2. The metal screw hole may be squeezed, resulting in a zero-boundary state of grounding and ungrounding, resulting in a strange abnormality in the system. The plum blossom hole, no matter how the stress changes, can always keep the screw grounded

　　 Cross flower pad:

　　 1. If the pad is the bottom wire, the cross-pattern pad can reduce the area of the ground wire, slow down the heat dissipation speed, and facilitate soldering.