Why PCB inspection is important in PCB assembly process?

Common PCB inspection processes

1.Manual PCB inspection: As the name implies, it involves manually looking at assemblies to inspect them for problems.

2.AOI PCB inspection: Automatic or automated optical inspection involves using an optical system that takes an image of the PCB assembly and to identify any flaws.

3.AXI PCB inspection: With density of PCBs increasing not all solder joints may be visible. Optical inspection therefore may not serve the purpose. In such cases an X-Ray system – AXI, is able to look under the chips to view the solder joints.

4.X-Ray Inspection: X-ray inspection is ideal for more complex boards & provides capabilities that other inspection methods can’t. The X-ray inspection will let you see inside solder joints to reveal bubbles that you can’t see using AOI

Let us look at some defects that can be easily pointed out using some of these PCB inspection techniques:

1.Blind or Buried Vias

2.Errors in landing patterns

3.BGAs

4.Decoupling Capacitors

5.Solder Voids

6.Pin-Hole Fills

PCB inspection comes with a wide range of benefits and ensures quality control of PCB. In fact, inspection of PCBs can help improve the overall PCB production process. If a particular defect tends to occur repeatedly, you can correct the flaw at the process level itself. Looked at in this manner, PCB inspection plays an important role in the continuous improvement of the PCB production process.
While it may be tempting to look at it like a cost, the fact remains that the cost of failure of products can be far higher, in the absence of inspection. Inspecting PCBs can uncover any defects. In fact, checking PCBs after each phase can help uncover flaws before moving to the next stage.The inspection method can help you ensure consistent quality across boards. Without a proper inspection protocol in place, flawed boards could reach the market. Especially if the defects are found out after the products have been shipped out, you not only may need to deal with expensive recalls, you will also have to face a costly loss in reputation. Worse still, a defective PCB can lead to injury or death, particularly if it is being used in a medical device or an automotive component.
From manual visual inspection to Automated Optical Inspection, X-Ray inspection, PCB functional testing and more, the wide range of inspection techniques ensure adequate performance while maintaining acceptable cycle times. Determining the best techniques for the needs of your project can go a long way in ensuring PCB integrity.