With the rapid development of integrated circuit technology, the number of layers of the circuit board from the initial single and double board development is more than a dozen or even higher multilayer board. So this is a lot of people to distinguish PCB layer brings many difficulties. When the number of layers, the more difficult to distinguish PCB layers. Therefore, it is necessary to grasp a kind of method to distinguish the PCB layer quickly.
The substrate of the circuit board is made of insulating and heat insulating material which is not easy to bend. The fine lines can be seen on the surface of the material is copper foil, copper foil is originally covering the entire circuit board, and in the manufacturing process partly etched off, left to the part of a network of thin wires. These lines are called wires or wires and are used to provide circuit connections on the circuit board. Usually the color of the circuit board is green or brown, which is the color of the solder mask. It is an insulated protective layer that protects the copper wire and prevents the parts from being soldered to the wrong place. Now the motherboard and graphics cards are multilayer board, greatly increasing the area can be wired. The multilayer board is provided with a plurality of single or double wiring boards, and a layer of insulating layer is placed between the layers to be pressed. The number of layers on the PCB board is represented by several layers of independent wiring layer, usually the number of layers is even, and contains the outermost two layers, the common PCB board is generally 4 to 8 layers of structure. A lot of the number of layers of the PCB board can be viewed through the PCB board to distinguish the number of PCB layers. But in fact, no one can have such a good eyesight.
The circuit board is connected through a multi-layer buried hole and blind hole, the motherboard and display card mostly use PCB board 4, and some with 6, 8, or even 10 layer PCB board. In order to distinguish PCB layer, through holes can be observed by identification, because in the motherboard and display card 4 plates are used on the first and fourth layers of wire, the other layer for other purposes (ground and power). So, with the same plate, the hole will be pierced through the PCB board. If some of the holes in the face of the PCB board appears, but can not find in the opposite, then it must be 6/8 laminates. If the PCB board can be found on the same side of the hole, is naturally the 4 board. Resolution of the PCB layer tips: the motherboard or display card to the light source, if the location of the guide hole can be transparent, it means that the 6/8 board; otherwise, the 4 layer.