Keyword: tube PCB, PCB circuit boards
What are the essential part of tube PCB? Below small make up for everyone to introduce an essential part of the tube PCB. The tube PCB circuit boards, mainly composed of the following:
Line and drawings (Pattern) : line is as original conduction between tools, the design will be another big copper surface as the grounding and power supply layer. Line and the surface is made at the same time.
Dielectric layer (Dielectric) : used to keep the lines and insulation between the layers, known as base material.
Hole (Through hole/via) : guide hole can make two or more layers of conducting lines each other, larger guide hole is used as parts plug-in, in addition, there are the guide hole (nPTH) is usually used as surface-mount positioning, fixed screw assembly.
Prevent welding ink (Solder resistant/Solder Mask) : not all the copper surface to Solder on the parts, so the Solder area, can print Solder material cut off a layer of copper surface (usually) of epoxy resin, avoid the Solder short circuit between the lines. According to the different process, divided into green oil, red oil, blue.
Screen printing (Legend/Marking/Silk screen) : this is a necessary composition, main function is in the circuit board on the parts name, location, box, convenient maintenance and identification after assembly.
Surface treatment, Surface Finish) : due to the copper Surface in the general environment, it is easy to oxide, tin lead to can't bad (solder), thus to protect in the aspect of eat tin copper. Protection way with Tin (HASL), gold (ENIG), and the Silver (based Silver), the Tin (based Tin), organic flux (OSP), methods each have advantages and disadvantages, referred to as surface treatment.
Source: //www.seekic.com
