There are currently five main PCBA testing methods:
1. Manual visual inspection
Manual visual inspection uses human vision and comparison to confirm the placement of electronic components on PCB circuit boards. This technology is one of the most widely used online inspection methods. However, with the increase in output and the shrinkage of PCB circuit boards and electronic components, this method is becoming less and less applicable. Low upfront costs and the absence of inspection fixtures are its main advantages. At the same time, high long-term costs, discontinuous defect detection, difficulty in data collection, no power inspection and visual limitations are also the main disadvantages of this method.
2. Automated Optical Inspection (AOI)
This inspection method is also called automatic visual inspection. It is usually used before and after PCBA reflow soldering. It is a newer method for confirming manufacturing defects. It has a better inspection effect on the polarity of components and the presence of components. It is a non-electric, fixture-free online technology. Its main advantages are easy to follow diagnostics, easy program development and no fixtures. The main disadvantage is that it has poor short-circuit identification and is not a power detection.
3. Functional Test
PCBA function detection is the earliest automatic detection principle. It is a basic detection method for a specific PCB or specific unit and can be completed with various detection equipment. There are two main types of functional testing: Final Product Test and Hot Mock-up.
4. Flying-Probe Tester
Flying probe inspection machine, also called probe inspection machine, is also a commonly used inspection method. It has gained widespread popularity over the past few years due to advances in mechanical precision, speed and reliability. In addition, the current requirements for inspection systems with fast changeover and fixture-free capabilities required for prototype manufacturing and low-volume manufacturing make flying probe inspection the best choice. The main advantages of flying probe inspection machines are that it is the fastest time to market tool, automatically generates inspections, has no fixture costs, good diagnostics and easy programming.
5. Manufacturing Defect Analyzer (MDA)
MDA is a great tool for diagnosing only PCBA manufacturing defects in high volume/low mix environments. The main advantages of this detection method are low upfront cost, high output, easy follow-up diagnosis and fast and complete short circuit and open circuit detection. The main disadvantages are that functional testing cannot be performed, there is usually no testing coverage instruction, fixtures must be used, and testing costs are high.