PCB and PCBA are important components of electronic products. The major difference between a PCBA and a PCB is that a PCBA is a bare PCB with electronic components mounted on it.
Testing is required after PCB manufacturing and PCB assembly to ensure that the PCB and later the PCBA products meet high quality specifications.
What standard tests are required for bare PCBs?
1. Visual Inspection
This is a basic check after PCB manufacturing, using automatic optical inspection (AOI) equipment to check whether the printed circuit patterns, pads, vias, etc. are manufactured in accordance with the design drawings.
2. Microtome Analysis
This is a method of examining the internal structure of a PCB by cutting a cross-section of the PCB to assess the internal interlayer connections and through-hole filling. 3.
3. Solderability Test
This is a test to check whether the pads on the PCB can be soldered correctly.
4. Electrical Test
Flying probe test checks that all expected electrical connections on the PCB are correct.
5. Impedance Test
If it is a high frequency PCB, it needs to be tested for impedance to maintain a specific impedance value.
6. Thermal Shock Test
Expose the PCB to extreme temperature changes to check for thermal damage or performance degradation.
What standard tests are required for PCBA?
1. Automated Optical Inspection (AOI)
Scanning the surface of an assembled PCBA with a high-resolution camera to detect soldering defects, missing components and misalignment.
2. X-ray Inspection
Particularly used for detecting invisible solder joints such as ball grid arrays (BGAs). X-rays allow you to see inside the PCB to check for soldering problems, bridges, shorts, and other issues.
3. In-Circuit Testing (ICT)
Verify the electrical performance of circuits using bed-of-nails test equipment to check each point in the circuit individually, looking for opens, shorts, resistors, capacitors, inductors, diode defects, and more.
4. Functional Testing
Tests to ensure that products function properly in the actual operating environment.
This is a test that places the PCBA in a high-temperature environment for a long period of time to simulate different environmental conditions in order to detect the durability and reliability of the PCBA.
These tests are conducted according to the International Printed Circuit Association (IPC) standards, which are the main criteria for PCB and PCBA quality and acceptance. Ensure that none of these tests are faulty, then a qualified PCB/PCBA can be officially shipped out of the factory.