Seektronics

In order to ensure the quality of PCBA, PCBA transportation and storage should also strictly comply with the operating specifications.   　   1 .  Anti-static   Do a good job of PCBA anti-static measures, the use of appropriate containers, tools, etc.   2 .  Use suitable transportation tools   Tools should ensure good, such as wheels, frames, etc.; abnormal should be reported in time to repair, prohibit the use of "with injury", so as to avoid the transport of semi-finished products fall, extrusion and other situations.   3 .  Check the common tools   Transport tools, storage tools, and workstations such as storage before the operation to do a good job of cleaning, do not allow debris, slag, etc.. Avoid damage to the PCBA caused by mutual friction.   4 .  Marking important information   Transportation, and storage of PCBA containers, and tools should be well marked on the car, record product-related information, to avoid misplacement, mixing, etc.   5 .  Stacking requirements

  Electronic devices will generate a certain amount of heat when working, so that the internal temperature of the device rises rapidly, if the heat is not distributed in a timely manner, continued heating, the device will fail due to overheating, the reliability of electronic equipment performance will be reduced. Therefore, a good thermal treatment of PCB circuit boards is very important.         1.  PCB heat dissipation itself   PCB heat dissipation is a simple, practical, low-cost way to dissipate heat. The current PCB circuit board is mainly: copper/epoxy glass cloth substrate or phenolic resin glass cloth substrate, although these substrates have excellent electrical properties and processing performance, but poor heat dissipation can hardly be expected to conduct heat by the PCB itself resin. Therefore, it needs to be designed to dissipate heat from the surface of the component to the surrounding air.   So how to do it? The best way to improve the direct contact with the heat-gen

  A good circuit board, in addition to achieving the principle function of the circuit, but also considers EMI, EMC, ESD (electrostatic discharge), signal integrity and other electrical characteristics, but also to consider the mechanical structure, the heat dissipation of large power consumption chips, on this basis and then consider the aesthetic issues of the board, just like the art of carving, deliberate on every detail of it.   Common PCB layout constraints principles   In the layout of PCB components often have the following considerations.   (1) Does the PCB board shape match the whole machine?   (2) Is the spacing between components reasonable? Are there any horizontal or height conflicts?   (3) whether the PCB needs to be put together? Is the process edge reserved? Are the mounting holes reserved? How to arrange the positioning holes?   (4) How to place the power module and heat dissipation?   (5) Is it convenient to replace the components that need to be replaced frequently?

  Stripping   In the production of PCB boards, there are only two steps in which stripping is used. The D/F stripping process is simple, using horizontal equipment, and the chemical solution used is mostly 1~3% NaOH or KOH by weight.   Line etching   1. The mechanism of copper etching   (1) copper ions in the alkaline environment solution is easy to form copper hydroxide precipitation, in order to prevent this precipitation phenomenon, you need to add enough ammonia to make the wrong ion group to produce ammonia copper to inhibit the precipitation occurs. It also allows the copper's original amount and its continued dissolution in the liquid to form a very stable wrong ammonia copper ion. Such divalent copper ammonia ion can be used as an oxidizing agent to dissolve the zero-valent copper metal by oxidation. Still, during the redox reaction, monovalent copper ions will be produced.   In this reaction, the solubility of sub-copper ions is very poor, it needs to be assisted by ammoni

Many people have encountered the situation of being rejected for small quantities when asking about SMT, and most of the reasons given for the rejection are "small quantities are not cost-effective" and " High  start-up losses". What are the so-called losses? Before SMT processing, you need to do the same preliminary work as when you receive a large order, such as SMT machine programming, PCB positioning, start the first piece of confirmation of this type. In the case of a small amount, the so-called loss, more is the loss of time. Because in the same time, the production efficiency of SMT with large processing volume is higher, so as not to waste time on the preliminary work after a morning or a day of production. And in the machine in and out of the time, so we prefer to receive the kind of area is not very large, but the patch point is very concentrated, so that both high efficiency, but also greatly save a variety of labor costs, machine losses, etc.   To quote