Circuit board inspection is an important part of the PCB assembly process. Testing during and after assembly ensures the boards will perform in the field and cuts down on recalls and post sale product repairs. With electronics forming an integral part of our everyday lives, we need to have confidence that these devices won’t let us down. A reputation for reliability goes a long way toward building a loyal customer base.
Circuit Board Inspection Steps
For boards assembled with Surface Mount Technology, the first inspection comes after the boards have passed through the reflow oven, soldering them in place. If any of the components moved during the reflow process, this will create a poor or missing connection. Shorts are also a common side effect of movement, as misplaced components can create connections on the circuit that do not belong.
Inspecting for errors and misalignments is most commonly performed manually, through AOI (Automatic Optical Inspection) or via X-ray inspection. Manual checks are most effective for small batches and become impractical and inaccurate as the number of boards to be inspected increases. AOI machines are more appropriate for large batches of PCBs, as they can process high quantities of PCBs in a relatively machines. These machines have cameras at different angles that allow them to view solder connections. Different quality solder connections reflect light differently, allowing the AOI machine to recognize a lower-quality solder. X-ray inspection is a less common inspection method, mainly used for complex or layered PCBs as the x-ray can see through layers and highlight potentially hidden problems.
Once assembly is completed, PCBs are put through functional testing before they are shipped. This inspection simulates the normal circumstances under which the PCB will operate. Power and simulated signals are passed through the PCB while testers monitor the PCB’s electrical characteristics. If any of those characteristics – including voltage, current and signal output – show unacceptable fluctuation or hit peaks outside a predetermined range, the PCB has failed.
Regular circuit board inspection and testing throughout the PCB assembly process is critical to ensuring the quality of boards produced. It also allows problems to be found and fixed quickly when it is least costly and disruptive to production times. Good PCBs are a product of good inspection methods.
Telan Corp: Producing High-Quality PCBs for Over 35 Years
In today’s cut-throat technological industry, a reputation for quality is key to staying on top. Trust your company’s reputation to an experienced PCB assembly service. At Telan, we have rigorous circuit board inspection standards, ensuring you get quality products, every time. For more information on our assembly services, call us today at 215-997-7603.
