Single panel

　　On basic medical PCB boards, the parts are concentrated on one side, while the wires are concentrated on the other side. Due to the fact that the wires only appear on one side, this type of medical PCB board is referred to as single sided. Due to the many strict restrictions on the design of a single sided circuit board (as it only has one side, the wiring cannot cross and must revolve around a separate path), only early circuits used this type of circuit board.

　　Double-sided board

　　This type of circuit board has wiring on both sides, but if wires are used on both sides, there should be appropriate circuit connections between the two sides. The "bridge" between these circuits is called a through hole. Through holes are small holes filled or covered with metal on medical PCB boards, which can be connected to wires on both sides. Because the area of a double-sided board is twice that of a single panel, it solves the problem of staggered wiring (which can be transmitted to the other side through vias). More suitable for more complex circuits than single panels.

　　Multilayer board

　　In order to increase the area that can be wired, multi-layer boards use more single or double-sided wiring boards. Use 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 of the printed circuit board. The printed circuit board with alternating positioning system and insulation bonding material, and interconnected conductive patterns according to design requirements, becomes a four or six layer printed circuit board, also known as a multi-layer medical PCB board. The number of layers of a board does not necessarily mean that there are several independent wiring layers. In special cases, add an empty layer to control the thickness of the board. Usually, the number of layers is even, including two outer layers. Most motherboards have a structure of 4 to 8 layers, but technically speaking, they can be medical PCB boards with nearly 100 layers. Most large computers use quite multiple layers of motherboards, but due to the fact that these types of computers can be replaced by clusters of many ordinary computers, multi-layer boards are gradually no longer used. Due to the close integration of various layers in medical PCB boards, it is usually difficult to see the actual quantity, but if you carefully observe the motherboard, you can still see it.