Category Archives: Design


Nov13
Why BGA soldering ball always crack(3)? IMC layer growth is a certain result to form the soldering joints

The Intermetallic Compound (IMC) layer grows in the interface between Cu-based, Ni-based and Sn-solder is the certain result of the chemical reaction that forming the soldering joint. But the IMC layer is also the most weakness location of the solder … Continue reading

Oct30
Why BGA soldering ball always crack(2)? The composition of PCBA bonding-force

This article will talk about the composition of the PCBA bonding-force. The PCBA bonding-force actually contains many items and factors. But working-bear think we can refer to the conclusion of red-dye test to discuss it. The BGA red dye and … Continue reading

Sep25
Why BGA soldering ball always crack(1)? Stress > bonding-force

What is the actual root cause of  BGA ball cracked? Stress is greater than its bonding-forces. The root cause of BGA solder ball cracked is stress greater than bonding-forces. Stress is greater than bonding-force is the certain result of BGA … Continue reading

Jun19
Increase solder paste volume will improve the MLCC capacitor broken?

Recently WorkingBear got complaint from R&D and ask increase the solder paste volume on the MLCC (Multi-Layer Ceramic Capacitor)  component pads to improve the capacitor broken issue. R&D said he had verified that the capacitor’s footprint in the board design … Continue reading

Jan05
Comparison between shielding-can directly mount and shielding-clip/frame

Recently one of my top manager ask to mount the shielding-can or call shielding-cover directly on the Printed Circuit Board to instead of mount the shielding-clip or call shielding-frame on the board first then cover the shieling-can. He said this … Continue reading