What Do the Common SMD, SMT and BOM in Electronic Pocessing Mean?

SMT is surface assembly technology, also known as surface mount technology, which is the most popular skill and process in the electronic assembly industry.

The shape of SMD is rectangular sheet, cylindrical row or special shape, and its soldering ends or pins are manufactured in the same plane, and it is suitable for surface mounter attached electronic components Reflow soldering: pre-distributed to PCB circuit by re-melting paste-like solder paste onboard pads that complete the mechanical and electrical connection between surface mount component terminals or pins and printed circuit board pads.

SMT and SMD use the no-clean process in surface mount technology. The waste water discharged after product cleaning during the production process brings pollution of water quality, land and animals and plants. In addition to water cleaning, the use of organic solvents rich in chlorofluorohydrogen (CFC & HCFC) for cleaning also pollutes and damages the air and atmosphere. The residual cleaning agent on the machine board brings corrosion appearance, which seriously affects the product quality. Reduce cleaning process operation and machine maintenance costs. No-clean can reduce the damage caused by the assembly board (PCBA) during the movement and cleaning process. There are still some components that cannot be cleaned.

The amount of flux residue has been controlled and can be used in conjunction with product appearance requirements, avoiding the question of visual inspection of cleaning conditions. Residual flux has been continuously improving its electrical function to avoid any damage to the product from leakage current. The no-clean process has passed a number of international safety inspections, which proves that the chemical substances in the flux of the smt placement machine are stable and non-corrosive.

Therefore, it is also called product structure table or product structure tree. In some industries, it may be called a “recipe”, “element table” or other names. In MRP II and ERP systems, the word material has a broad meaning. It is a general term for all products, semi-finished products, work-in-process, raw materials, accessories, cooperative parts, consumables and other production-related materials.