PCB circuit boards can be seen everywhere in various electrical appliances and instruments. The reliability of circuit boards is an important guarantee to ensure the normal operation of various functions. to a large area of copper.
Generally speaking, large-area copper cladding has two functions. One is to dissipate heat. Due to the excessive current of the circuit board, the power rises. Therefore, in addition to adding necessary heat dissipation components, such as heat sinks and cooling fans, but for some circuit boards Relying on these is not enough, if it is only a simple heat dissipation effect, while increasing the copper foil area, it is necessary to increase the soldering flux layer, and add tin to enhance heat dissipation.
It is worth noting that due to the large-area copper cladding, the adhesion between the PCB board and the copper foil will be reduced after passing the peak or the PCB is heated for a long time, and the volatile gas accumulated in it cannot be discharged over time. The foil expands and falls off, so if the copper clad area is very large, you should consider whether there is such a problem, especially when the temperature is relatively high, you can open a window or design it as a grid.
The other is to enhance the anti-interference ability of the circuit. Since a large area of copper can reduce the impedance of the ground wire, it can shield signals and reduce mutual interference. Especially for some high-speed PCB boards, in addition to thickening the ground wire as much as possible, the necessary ground wires on the circuit board Spare areas must be grounded, that is, "full grounding", which can effectively reduce parasitic inductance and large-area grounding can effectively reduce noise radiation. For example, for some touch chip circuits, ground wires are spread around each button, which reduces the anti-interference ability, as shown in the figure below
