PCBA assembly manufacturers in the production process of each link may appear electrostatic damage components, and then lead to the failure of PCBA. Briefly introduce some common electrostatic related content in PCBA assembly production processing.
一、Static electricity and static electricity hazards
In the electronic assembly and processing industry, the generation of static electricity will bring serious harm and loss, PCBA assembly manufacturers have corresponding regulations on the design, manufacturing, procurement, warehousing, inspection, storage, assembly and debugging, semi-finished products and finished products packaging, transportation, etc., and there are more strict regulations on the manufacture, use and management of electrostatic protection devices.
二、 Electrostatic power supply for electronic assembly processing
1, Human skin and clothes, shoes, socks and other objects friction, contact and separation generated by static electricity, is one of the main electrostatic power sources for electronic products manufacturing.
2, Chemical fiber or cotton work clothes and work table, work chair friction, can produce more than 6000V electrostatic voltage on the surface of the clothing, and make the human body charged, at this time and the device contact, will cause discharge, the device is easy to damage.
3, The insulation resistance of rubber or plastic sole can reach 1013Ω, and the friction with the ground will produce static electricity, and make the human body generate electric charge.
4, Resin, paint film, plastic film packaged devices placed in the packaging and transportation, the surface of the device and the packaging material friction, can produce hundreds of volts of electrostatic voltage, so that the sensitive device discharge.
5, By PP(polypropylene), PE(polyethylene), PS(polyvinyl chloride), PVR(polyamine), PVC and polyester resin and other polymers made of various packaging, raw material boxes, turnover boxes, PCB racks, etc., can produce 1-3.5KV electrostatic voltage due to friction, impact, discharge sensitive plastic products.
6, The general work table, due to friction and static electricity. The insulation resistance of concrete, wax-polishing floor, rubber board and other insulating ground is high, and the static electricity in the human body is not easy to leak.
三、Electrostatic Sensitive Devices (SSD)
Components that are sensitive to electrostatic reactions are called electrostatic sensitive components (SSDS). Electrostatic sensitive devices mainly refer to very large scale integrated circuits, especially metallized thin film semiconductors (MOS). According to the SSD classification table, you can take different ESD preventive measures for different SSD devices.