Circuit board, which can be regarded as a miniature bearing platform, is an important carrier of integrated circuit. The appearance of PCB multilayer board allows the limited space to accommodate more and more complex circuits as much as possible. In addition, it also simplifies the difficulty of circuit layout on PCB to some extent. Many friends think: The more PCB layers, the better the performance. Is this true?
At present, the most common PCB multilayer board on the market is four or six layers. The higher the product precision, the higher the requirement for the number of layers of the circuit board. Like aerospace equipment, it is not surprising that the number of PCB layers is as high as several hundred.
The more layers of PCB, the higher the difficulty index of PCB wiring proofing, so the manufacturing cost is relatively high. However, this does not mean that the performance of high-level PCB is higher than that of low-level PCB. High-level PCB is just to make electronic circuits have more wiring space and ensure the optimal layout of subtle wiring. The higher the number of PCB layers, the lower the electromagnetic interference among the layers, thus reducing the interference between signals and prolonging the service life of PCB.
The performance of the circuit board can’t be equated with the number of layers. Simple four or six layers of PCB multilayer boards also have excellent performance. Actually, the number of circuit board layers is only a rigid requirement in circuit board design, and it is not used as a standard to judge whether a PCB is good or bad.
As the circuit board is mainly composed of raw materials such as corrugated fiber cloth, resin and copper foil, and the material itself has a certain thickness, the higher the number of layers of PCB multilayer board, the more the layers of these raw materials will accumulate. Therefore, to a certain extent, PCB multilayer board is more rigid than single-layer and double-layer board.
Due to the different technical capabilities of each PCB factory, the total number of components that can be reasonably accommodated on each floor is also different. Theoretically, within a reasonable range, there is no difference in performance between mounting 100 components on one PCB and mounting them on two PCB boards separately. However, at present, the volume demand of electronic products is getting smaller and smaller, which requires the design space to be smaller and the volume of circuit boards to be smaller and smaller with the same performance.
Therefore, to sum up, the higher the number of layers of PCB multilayer board does not mean the better performance, so it should be designed according to its own use requirements.
