As we all know, in electronic engineering, PCB design occupies a particularly important position. PCB design will directly affect the EMC performance, output noise, anti-interference ability of the power supply, and even affect the basic function of the power supply. PCB wiring in power supply is slightly different from other hardware. How to design PCB line in power supply? What should we pay attention to? Next, follow us to understand clearly.
1.Spacing
For high voltage products, line spacing must be considered. Of course, the spacing that can meet the requirements of the corresponding safety regulations is the best, but in many cases, for products that do not need certification or cannot meet the certification, the spacing is determined by experience.
How big is the right space? It is necessary to consider whether the production can ensure the cleanliness of the board, environmental humidity and other pollution, etc. For the market power input, even if the board surface is clean and sealed, the leakage source of MOS tube is close to 600 V, less than 1 mm is actually dangerous!
2、 Edge part of plate
At the edge of PCB chip capacitor or other vulnerable components, the direction of PCB distributor must be considered when placing. As shown in the figure of various placement methods, the stress of components must be compared.
3、 Loop area
No matter input or output, power loop or signal loop should be as small as possible. The power loop emits electromagnetic field, which leads to poor EMI characteristics or high output noise. At the same time, if it is received by the control loop, it is likely to cause an exception.
On the other hand, if the power loop area is large, the equivalent parasitic inductance will increase, which may increase the drain noise peak.
