The importance of 100% testing for quality assurance in PCB manufacturing

The importance of 100% testing for quality assurance in PCB manufacturing

If you want to buy a printed circuit board (PCB), it always pays to make sure your board is 100% tested. If you search the Internet for the reasons why the PCB is not working, you will find that there are several reasons; Any one of them may be difficult to troubleshoot. Testing the board 100% before a problem arises is a much more valuable option.

Think of it this way - a 100% tested circuit board will give buyers confidence in the quality, reliability and durability of the product. Some reasons to only buy from manufacturers that test 100% of their boards include:

Proof prototype

When designing a circuit board, always prototype it. These prototypes are trials of the final PCB, to be manufactured in the short term. Before commissioning the print, the designer will iteratively test the prototype to ensure that it meets all design specifications and expected results. Once all the details of the board meet the specifications, the designer is confident in the manufacture.

While the process of printing and testing prototypes can be expensive and time-consuming, there is significant value in ensuring that the PCB is error-free before full-scale production. A range of issues can be identified through this testing process, such as reversing polarity, identifying short circuits, and identifying any missing components.

Automatic optical inspection

Automatic Optical Inspection (AOI) is the automatic visual inspection of the PCB. The camera will scan the PCB to identify issues such as missing components and quality defects. The digital image recorded by the camera is compared to the original design of the PCB. If there are any discrepancies, they can be corrected before printing.

Because AOI is a non-contact test method, it can be used at all stages of PCB manufacturing. When the solder paste is in place, the same circuit board can perform AOI as a bare board, both before and after reflow soldering. AOI will ensure that the layers are properly constructed before laminating the plates.

X-ray detection

Automatic X-ray Inspection (AXI) uses X-rays to automatically detect features that may be hidden from view. Like AOI, the goal of AXI is to optimize processes and detect anomalies. X-ray inspection can reveal the smallest defects in the PCB. This is especially true for defects that may be overwritten by other components. Failures that can be identified include incorrect assembly installation, internal cracks, lamination problems, and porosity issues. The use of X-rays is invaluable because testing can easily identify defects, enabling designers to fix them before production.

Functional testing

Functional testing is usually the final test before production. A trained quality control engineer tests the circuit board to determine if the components are working properly; And whether the PCB is producing the desired results.