Defects in wave soldering of PCB pad
Common PCB welding pad over wave soldering defects have the following points: (1) board surface dirty. (2) PCB deformation. (3) drop (drop) the piece. (4) Other recessive defects.
Common PCB welding pad over wave soldering defects have the following points: (1) board surface dirty. (2) PCB deformation. (3) drop (drop) the piece. (4) Other recessive defects.
In the dispensing process, the technical parameters of the patch glue and the dispensing machine can be changed as follows: (1) the rheology of the patch glue. (2) The initial adhesive strength of the patch adhesive. (3) glue point contour. (4) glue point
A perfect PCB board not only needs to do the component selection and setting is reasonable, but also needs to have good signal conduction performance.
10 advantages of soft PCB: flexibility, reduce volume, reduce weight, consistency of assembly, increased reliability, electrical parameter design controllability, the end can be the whole solder, material use option, low cost, continuity of processing.
The simplest multilayer soft PCB is a three-layer soft PCB formed by two layers of copper shielding on both sides of a single-sided PCB. The most commonly used multilayer soft PCB structure is the four-layer structure.
Some measures can be taken to clean the tail of PCBA production and processing to improve work efficiency: 1. About 40pcs of PCB board shall be checked and signed by the quality engineer before the product comes off the line. 2. The operator or inform the
The physical treatment of waste PCB mainly includes mechanical crushing, air separation, magnetic adsorption and other technologies; Chemical method is divided into pyrometallurgy, hydrometallurgy and so on.
To summarize, the production process of a typical pcb factory is as follows: blanking → inner fabrication → pressing → drilling → copper plating → outer fabrication → soldering paint printing → text printing → surface treatment → contour processing.
In 1936 a radio was built with a printed circuit board. In 1943, PCBS were widely used in military radios. In 1948, PCBS were officially approved for commercial use. On June 21, 1950, Paul Essler was granted a patent for his invention.
The milling technology of circuit board CNC milling machine includes the selection of cutting direction, compensation method, positioning method, frame structure, the next cutter point, which is an important aspect to ensure the milling precision.
Five common silver plating defects of multilayer circuit boards have been solved by solution manufacturers, equipment manufacturers and PCB factories, and some methods have been found to prevent and improve them.
The number of layers of the multilayer board is not limited, there are more than 100 layers. Relatively speaking, PCB with even layers does have more advantages than PCB with odd layers.