A multilayer use more single or double wiring board
Static measurement: if there is no physical deformation after processing circuit board shape, the internal manuscript there may be a problem.
Professional circuit board processing and testing organizations will use a multimeter to measure an orderly internal components, circuit board to see whether there are other problems, such as short circuit.
In this step, should pay special attention to ensure that the power supply is normal, and avoid secondary circuit board burn.
Circuit board oxidation (
Life is very long)
Professional circuit board after processing, antioxidant, thermal shock and the characteristics of moisture.
Under normal circumstances is not easy to rust, oxidation or sulfide.
SMT plug-in processing, this method can make a exposed clean copper surface in a very short period of time with molten solder together, immediately to become solid solder joints.
SMT plug-in processing strictly according to customer requirements for processing the PCB plate blanking, type error, epsilon r wrong, thickness error, PCB manufacturing process can also, also destroyed.
Because epsilon r had a great influence on the Z0, finished products profes sional should avoid water absorption, as far as possible because epsilon r = 75 water can bring a big decline to Z0 and unstable.
Sandwich plate in order to increase the area of the wiring, a multilayer use more single or double wiring board.
In a double lining, two single side as the outer layer, or two double as inner lining, two single side as the outer layer, the positioning system with flange and adhesive materials used interchangeably interconnect PCB into four layers and six layer printed circuit board, also known as multilayer printed circuit boards.
Circuit board layer does not mean that there are several independent wiring layer.
Under special circumstances, will add an empty layer to the thickness of the panel.
Usually, the even number of layer, including two outer layer.
Most mainboards has four to eight layer structure, but technically, it can achieve nearly 100 layers of PCB.