What is a multilayer PCB  Board?

What is a multilayer PCB  board? What are the characteristics of multilayer PCB?

PCB is usually named by how many circuit layers there are. The simplest single-sided PCB board means that there is only one layer. The double-sided PCB only has lines on the upper and lower sides, and the two-layer connection is realized through metalized holes. The multilayer PCB is made up of three or more double-sided boards stacked, alternated by positioning systems and insulating adhesives, and conductive patterns are interconnected according to design requirements. Multi-layer PCBs are connected by metal holes, but there are more types, such as buried vias and blind vias.

The biggest difference between PCB multi-layer boards and single-sided and double-sided boards is the addition of internal power and ground layers. The power and ground networks are mainly routed on the power layer. Each substrate layer in a PCB multi-layer board has conductive metal on its two sides, and a special adhesive is used to connect the boards together, and there is an insulating material between each board. However, PCB multilayer wiring is mainly based on the top and bottom layers, supplemented by the middle wiring layer. Therefore, the design of multi-layer PCB boards is basically the same as the design method of double-sided boards. The key is how to optimize the wiring of the inner electrical layer to make the wiring of the circuit board more reasonable. The inevitable product of the development of multi-function, large capacity and small volume. With the continuous development of electronic technology, especially the extensive and in-depth application of large-scale and very large-scale integrated circuits, multi-layer PCBs are rapidly developing in the direction of high density, high precision, and high-level digitalization. Fine lines, small aperture penetration, and blind Technologies such as hole-buried hole and high plate thickness-to-aperture ratio can meet the needs of the market. PCB multilayer printed boards have been widely used in the manufacture of electronic products for their flexible design, stable and reliable electrical performance and superior economic performance.