7. Micro-via technology allows the carrier board design to shorten the distance between grounding and signal layers, thereby improving RF/electromagnetic wave/electrostatic discharge (RFI/EMI/ESD) interference. The number of grounding wires can be increased to prevent the damage of components caused by instantaneous discharge due to static electricity accumulation.
2. Welding defects caused by warpage Circuit boards and components are warped during the welding process, and defects such as virtual welding and short circuits are generated due to stress deformation. Warpage is often caused by an unbalanced temperature between the upper and lower parts of the board. For large PCBs, warping will also occur due to the board’s own weight falling.
3. The PCB board has oxidation phenomenon, that is, the pad is black and not bright, and the oxidation phenomenon can be removed by an eraser. Generally, when the PCB is damp, the small batch processing factory of SMT proofing is placed in a drying oven for drying. If there are oil stains, sweat stains and other contamination on the board, clean it with absolute ethanol.
2. External performance: 1. Good wettability, the edge of the welding point should be thin; 2. The surface of SMT solder joints with good quality is complete and smooth and bright; 3. The appropriate amount of solder and the solder completely cover the soldering parts of the pads and leads, and the height of the components is moderate.