The so-called copper pouring is to use the idle space on the circuit board as the reference plane, and then fill it with solid copper. These copper areas are also called copper pouring.

　　The meaning of copper cladding on the circuit board is to reduce the ground wire impedance and improve the anti-interference ability; reduce the voltage drop and improve the power supply; connect to the ground wire and reduce the loop area. Also for the purpose of keeping the PCB from being deformed as much as possible during soldering, most PCB manufacturers also require PCB designers to fill the open area of the PCB with copper or grid-like ground wires. If the copper cladding of the circuit board is not handled properly, it will not be worth the loss. Is the copper cladding "pros outweigh the cons" or "the harm outweighs the pros"?

　　We all know that in the case of high frequency, the distributed capacitance of the wiring on the printed circuit board will have an effect. When the length is greater than 1/20 of the corresponding wavelength of the noise frequency, the antenna effect will occur, and the noise will be emitted through the wiring. If there is a poorly grounded copper cladding in the PCB, the copper cladding will become something that transmits noise. Therefore, in a high-frequency circuit, do not think that if a certain part of the ground wire is grounded, this is the "ground". "Line" must be made with a spacing of less than λ/20, through holes in the wiring, and "good grounding" with the ground plane of the multi-layer circuit board. If the copper cladding is handled properly, the copper cladding not only has the effect of increasing the current, but also has the dual effect of shielding interference.

　　There are generally two basic ways of copper cladding on circuit boards, that is, large-area copper cladding and grid copper cladding. People often ask whether large-area copper cladding is good or grid copper cladding is good, and it is not good.

　　why? Large-area copper cladding has the dual effects of increasing current and shielding, but large-area copper cladding may cause the circuit board to warp or even bubble if it is over-wave soldered. Therefore, for large-area copper cladding, several slots are generally opened to alleviate copper foil blistering. The simple grid copper cladding is still mainly for the shielding effect, and the effect of increasing the current is reduced. From the point of view of heat dissipation, the grid has The benefit (it reduces the heating surface of the copper) also has a certain electromagnetic shielding effect.

　　However, it should be pointed out that the grid is composed of traces in staggered directions. We know that for circuits, the width of the traces has its corresponding "electrical length" (the actual size divided by the operating frequency of the circuit board). It can be obtained by the digital frequency corresponding to the operating frequency, see related books for details). When the operating frequency is not very high, the effect of grid lines may not be very obvious. Once the electrical length matches the operating frequency, it will be very bad. You It will be found that the circuit is not working properly at all, and signals that disturb the operation of the system are being emitted everywhere. Therefore, for colleagues who use grids, it is recommended to choose according to the design of the circuit board operation, and do not cling to one thing. Therefore, high-frequency circuits are used for multi-purpose grids with high anti-interference requirements, and circuits with large currents in low-frequency circuits are commonly used in good copper.

Read recommendations:

Six-layer Immersion Gold Board (BGA)

High frequency PCB

Six-layer Immersion Gold Board (BGA)

Six-layer Immersion Gold Board (BGA)

Mobile phone template (six layers)