PCB circuit board is the support of electronic components and the provider of electrical connection of electronic components. According to the number of circuit layers, it can be divided into single panel, double-sided board and multilayer board. The common multilayer board is generally 4-layer board or 6-layer board, and the complex multilayer board can reach more than ten layers. Here is a brief introduction:

Single panel

Single side boards are on the most basic PCB. Parts are concentrated on one side and wires are concentrated on the other side. Because wires only appear on one side, this kind of PCB is called single side. Because there are many strict restrictions on the design circuit of a single panel (because there is only one side, the wiring cannot cross and must go around a separate path), only early circuits used this kind of board.

Double sided board

Double sided boards have wiring on both sides of the circuit board, but to use wires on both sides, there must be appropriate circuit connections between the two sides. This "bridge" between circuits is called a via. The guide hole is a small hole filled or coated with metal on the PCB, which can be connected with the wires on both sides. Because the area of the double-sided board is twice as large as that of the single panel, the double panel solves the difficulty of staggered wiring in the single panel (it can be connected to the other side through holes), and it is more suitable for more complex circuits than the single panel.

Multilayer board

Multi layer boards in order to increase the area of wiring, multi-layer boards use more single or double-sided wiring boards. A printed circuit board with one double-sided as the inner layer, two single-sided as the outer layer, or two double-sided as the inner layer and two single-sided as the outer layer, which is alternately connected together through the positioning system and insulating bonding materials, and the conductive graphics are interconnected according to the design requirements, becomes a four layer and six layer printed circuit board, also known as multi-layer printed circuit board.