5 PCB Assembly Problems & How to Solve Them?
PCBA is a very important step of the whole PCB manufacturing process. According to industry statistics, the top 3 PCB assembly defects which account for 74% of all manufacturing defects are Opens, Solder bridging, and Component shift. Minimization of all solder joint defects should be the goal for any SMT manufacturer. Through understanding the defect, its root causes, as well as how to prevent it, you can greatly improve the quality of all assemblies you manufacture. In this passage, we are providing the details of 5 PCB assembly problems and how to solve the problems. If you are going to learn the knowledge please check and read the content below for more.If you want to order PCB product, please check and custom your order online. 1. What is Plating Voids? – How to solve it? Plated through holes are important holes on the printed circuit board, as they carry electricity from one side of the board to the other side through the holes. The walls of these holes are electroplated during the PCB fabrication process. Before electroplating, the circuit board is made conductive from the top to bottom by copper deposition. In this process, the electroless copper is made to adhere to the edges of the circuit board and within the holes. The problems with copper deposition give rise to plating voids, which means the walls are not coated evenly with copper. These holes may affect the flow of electricity. Plating voids may be caused due to a variety of reasons such as material contamination, air bubbles in the material, contaminated holes, and so on. So, the defects caused due to air bubbles, contamination, and insufficient cleaning can be avoided by cleaning the material before drilling. Also, other defects can be avoided by following the directions provided by the manufacturer.2. What is Physical Damage? – How to solve it? Failure of PCB is linked to physical damage, which is caused due to environmental stresses or during the SMT manufacturing process. Most common cause of PCB failure is dropping a circuit board in a prototyping phase. The damage to the physical components or pieces is not easily visible, and they are not repairable either. Thus, there is no other option except replacing the PCB.3. What is Component shift? – How to solve it? The component shift means poor alignment of PCBs parts to their intended target. Components shifts are one of the most common manufacturing defects that PCB assemblers face. It mainly occurs during reflow as parts tend to shift and move on the molten hot solder. Some parts may end up misaligning themselves. It is because of tension that exists on the molten solder surface. Some other factors may also bring about a component shift. They include bent leads, massive convection rates, rapid vibrations in the conveyer, poor solder placement, and lopsided heat sinks on the components. But on the bright side, there are several ways that manufacturers can use to do away with cases of component shift when manufacturing their PCBs. It's advisable to ensure you maintain the right humidity. You should also ensure that you have the proper temperatures too. Also, manufacturers need to ensure the minimization of movement.4. What is Solder Joint? – How to solve it? Most of the solder the electronic industry uses today is of the lead-free variety, as use of lead has been recognized as a health hazard. Lead-free solder melts at a higher temperature, and has introduced a variety of challenges. Rush PCB has compiled a list of solder defects that can help managers, designers, engineers, and operatives recognize these everyday problems and allow them troubleshoot efficiently and effectively. The electronic industry uses the standard IPC 610D for the Acceptability of Electronic Assemblies. The standard offers criteria for lead-free soldering and has examples of typical process faults. The document is continually updated and will include more examples of lead-free soldering in the future.5. What is Pin and Connector Check? – How to solve it? Some essential components in a printed circuit board are pins and connectors. Pins/fasteners and connectors help in relaying signals during operation. Poor placement of the pins may bring costly damages to the connector. But to prevent such a case, it is vital to use a tool known as a pattern-matching to check the correct placement of the connectors. As a PCBA manufacturer, you can use this pattern-matching equipment to locate and group the patterns correctly. The pattern-matching tool is also ideal as it consists of a score indicating how much the patterns match the intended location or design. Better yet, to ensure proper pin alignment, you can go ahead and use telecentric lenses. A good reason for using telecentric lenses is due to its magnification that doesn't change. With such, manufacturers can prevent or do away with the problem of parallax error. The conventional lens can cause parallax errors. It becomes easier for manufacturers to avoid these defects by doing thorough checks of connectors and pins. Conclusion As a PCB user, it is frustrating receiving PCBs that functions, but only for a short time then fail. To a manufacturer, you'll end up spending much cash and waste even more time, especially in the event of recalls. Having a clear understanding helps you avoid the manufacture of low-quality boards. With high-quality boards, you'll enhance the reputation of your business. In the long run, it attracts more clients to partner with you.Wanna know PCB knowledge? Check and read for more.