Author Archives: WorkingBear


Sep05
Using 2D X-Ray to Diagnose BGA Solder Void Issues

post on September 5, 2024

This is an X-ray inspection image of an MCU’s BGA soldering that failed after reflow. The owner mentioned that the BGA package was not functioning, but when pressing on the MCU, it would temporarily work again. Since Workingbear didn’t have … Continue reading →

Quality, SMT, Soldering, Test/Inspection     WorkingBear    Views (1,500)     comment (0)
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Aug29
How to Use 2D X-Ray to Identify BGA Issues like Non-Wetting, Cold Solder, and HIP or NWO

post on August 29, 2024

If you’re an SMT engineer, you’ve probably used an X-Ray inspection machine to check the soldering quality of BGAs. But, after looking at the BGA solder balls repeatedly, they all seem to look the same. So, how can you tell … Continue reading →

Quality, SMT, Soldering, Test/Inspection     WorkingBear    Views (2,087)     comment (0)
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Aug22
What is ENIG Surface Finished for Circuit Boards? What Are Its Advantages and Disadvantages?

post on August 22, 2024

ENIG (Electroless Nickel Immersion Gold), also known as immersion gold (Au), chemical Ni/Au, or soft gold, is a type of surface finished for printed circuit boards (PCBs). It is widely used in the assembly of mobile phone circuit boards and … Continue reading →

PCB/FPC/PTF, Process, Quality, SMT, Soldering     WorkingBear    Views (2,105)     comment (0)
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Aug15
Causes of Poor Solderability on HASL Finished PCBs (Data Collection and Analysis)

post on August 15, 2024

Workingbear personally doesn’t recommend using HASL (Hot Air Solder Leveling) surface-finished PCBs in today’s SMT reflow processes, especially for double-sided reflow or fine-pitch components located on 2nd side. The defect rate of soldering with HASL is quite high and hard … Continue reading →

PCB/FPC/PTF, Process, Quality, SMT, Soldering     WorkingBear    Views (1,327)     comment (0)

Aug08
What Do PCB and PCBA Stand For? What’s the Difference?

post on August 8, 2024

What is the difference between PCB and PCBA? This should be an easy concept to understand, but since someone asked Workingbear, let’s explain it a bit. If you find any errors while passing by, please let us know to correct … Continue reading →

PCB/FPC/PTF, Soldering     WorkingBear    Views (1,172)     comment (0)