According to the circuit layers Category: divided into single and double panels and plywood. Common multilayer laminates usually 4, or 6 layers, complex multilayer boards up to a dozen layers.
PCB board are divided into three main types:
1, Single-Sided Boards in the most basic PCB, components concentrated in one side, wires are concentrated in the other side. Because the lead only in one side, so this is called single-sided PCB (Single-sided). Single-panel design lines because there are many strict restrictions (because only one side, wiring, there can not cross the path must be around alone), only the circuit until the early use of such a board.
2, Double-Sided Boards have both sides of this circuit board wiring, but with a wire on both sides, both sides must be in the proper electrical connections between the Caixing. This circuit between a "bridge" is called the pilot hole (via). Pilot hole in the PCB, the holes filled or coated with metal, it can be connected with the wires on both sides. Because the two-panel single panel bigger area than doubled, and because routing can be interlaced (which can be around to the other side), it is more suitable for use in more complex than the single-sided circuit.
3, Multi-Layer Boards can be routed in order to increase the area of multilayer spend more single-or double-sided wiring board. For the inner layer with a piece of double-sided, two-sided outer surface or two-sided as to make the inner layer, two-sided printed circuit boards for the outer layer, through the positioning system and the insulation and conductive adhesive materials alternately with graphics according to design requirements for interconnection of printed circuit boards to be four, six printed circuit board, and also known as multi-layer printed circuit board. Board represents the number of layers there are several layers of independent wiring layer, usually layers are even, and contains the most outer two layers. Most of the motherboard are 4 to 8 layers of structure, but the theory can be done technically almost 100 layers of PCB board. Most large-scale use of supercomputers rather multi-layered board, but because these computers have been available to replace many common computer clusters, super-multilayer has been gradually being used. Because the PCB levels are in close combination, generally not easy to see that the actual number, but motherboard If you look closely, you can still be seen.
Classified according to hard and soft: divided into ordinary circuit board and flexible circuit boards.