What is a multilayer PCB?
PCB can be classified into single-sided PCB, 2 layers PCB and multi-layer PCB according to the number of layers. There are many line layers in a multilayer PCB. The number of layers in a PCB does not mean that there are several layers of wiring. Sometimes empty layers are added to control the thickness and impedance of the PCB. Generally, the number of PCB layers is even.
A multilayer PCB can be defined as a PCB made of a multilayer copper foil conductive layer. Conductive copper foil appears to be the various layers of a multifaceted circuit PCB. Different layers are bonded together, then bonded together, and then heat protected with an interlayer insulation layer. Layers are placed in such a way that both sides of the PCB are on the surface. Holes are the source of electrical connections between different layers of a multilayer PCB. With the development and upgrading of the electronics industry, people feel that they need 4-layer PCB and higher-level PCB. Over time, problems with PCBs such as noise, crosstalk and stray capacitance have also been solved. PCB now has complex design and beautiful wiring, which makes it attractive in electronic devices.
The biggest difference between the multilayer PCB and the first layer PCB and the 2 layers PCB is that the multilayer PCB increases the internal power layer and the interface layer, but the multilayer PCB wiring mainly consists of the top and bottom layers, and the design method is basically the same as the 2layers PCB.
The principles to be followed in the design of multilayer PCBs are as follows:
1. Determine the shape, size and number of layers of a multilayer PCB.
2. Consider the position and placement of electronic components.
3. Consider the requirements for traverse layers and wiring zones.
领英推荐
4. Consider traverse alignment and PCB line width requirements.
5. Consider drill hole size and AD requirements.
6. Consider power layer, stratum zoning and pore requirements.
7. Consider the setting of safe traverse spacing.
8. Attention should be paid to the overall anti-interference capability of PCB.