Quality control is essential in PCB assembly. EMS manufacturers use different inspection technologies to identify defects early and prevent faulty products from reaching customers.
What Is SPI
SPI means Solder Paste Inspection. After solder paste printing and before component placement, SPI measures paste height, volume and alignment. It helps find printing problems before they cause soldering defects.
What Is AOI
AOI means Automated Optical Inspection. After components are placed and soldered, AOI captures images of the assembled board and compares them with expected patterns. AOI can detect missing components, wrong placement, polarity issues and solder defects.
What Is X-Ray Inspection
X-ray inspection is used when solder joints cannot be seen from the outside. It is important for BGA, QFN and other advanced packages. X-ray can reveal hidden solder bridges, voids and insufficient solder.
Why Inspection Matters
Automated inspection reduces dependence on manual checking and helps maintain consistency in high-volume production. Combined with functional testing and traceability systems, inspection supports reliable electronic manufacturing.
For audio products, TWS earbuds and compact PCBA modules, strong inspection capability is especially important because boards are small and component density is high.
Contact Heliance to learn more about our quality control and testing processes.