1. What is copper cladding?

The so-called copper-clad, is the circuit board idle space as a base level, and then filled with solid copper, these copper area is also known as copper. The significance of copper cladding is to reduce the impedance of ground wire, improve the anti-interference ability, reduce the voltage drop, improve the power efficiency, connect with ground wire, and reduce the area of loop road. Also for the purpose of minimizing distortion when soldering a PCB, most PCB manufacturers will also require PCB designers to fill the open area of the PCB with copper or grid-like ground wire. If the copper coating is not handled properly, it will not pay off, is Copper Cladding "more good than bad" or "more bad than good" ?

It is well known that at high frequencies, the distributed capacitance of the wiring on the printed circuit board acts. When the length is greater than 1/20th of the corresponding wavelength of the noise frequency, an antenna effect is produced, and the noise is emitted outwards through the wiring, if there is bad grounding in the PCB, copper cladding is a tool to spread the noise.

Therefore, in the high-frequency circuit, do not think that the ground to a certain place, this is the "ground" , must be less than/20 spacing, in the wiring on the hole, and multilayer board ground plane "good grounding. If the copper coating is properly treated, the copper coating not only increases the current, but also plays a double role of shielding interference.

2.forms of copper cladding

There are generally two basic ways of copper cladding, that is, large areas of copper cladding and copper grid, it is often asked, large areas of copper cladding or copper grid good, not a generality. And why is that? LARGE-AREA COPPER-CLAD, with increased current and shielding double effect, but large-area copper-clad, if the wave soldering, the board may be up, or even bubble. Therefore, a large area of copper-clad, general will open a few slots, to ease the copper foams. HERE'S THE CHART:

The effect of increasing the current is reduced. From the point of view of heat dissipation, the grid has advantages (it reduces the heating surface of copper) and also plays a role of electromagnetic shielding. This is especially true for touch and other circuits, such as the following:

It's important to note that the grid is made up of intersecting lines, and we know that for a circuit, the width of the Circuit Board for the operating frequency has its corresponding "electrical length" (actual size divided by the operating frequency of the corresponding digital frequency can be obtained, see the relevant books) . When the operating frequency is not very high, perhaps the effect of grid lines is not obvious, once the length of electricity and operating frequency match, it is very bad, you will find that the circuit is not working properly, everywhere is emitting interference system working signal.

Recommendations are based on the design of the Circuit Board working conditions, do not cling to a thing. Therefore, high-frequency circuit anti-interference requirements of the multi-grid, low-frequency circuit has a large current circuit, such as the common use of complete copper-laying. 

Source: 21ic electronic network