Awesome reballing Job

[ubm3d]

Awesome reballing Job in Detail: Just stumbled across that awesome video on youtube.

If you havent seen it yet, and love hardware - that is actually hardware porn

 

 

 

[SolarNova]

Was likely not the reballing that 'temporarily' fixed that, but rather the heat affecting the internals of the chip.

 

Any heat hot enough to affect the chip will melt the solderballs, this is why many people believe reballing works, when infact its just the heat.

 

That will likely die again within a year.

 

Still , its a cool thing to watch.

[bob345]

On 4/14/2019 at 7:05 AM, SolarNova said:

Was likely not the reballing that 'temporarily' fixed that, but rather the heat affecting the internals of the chip.

 

Any heat hot enough to affect the chip will melt the solderballs, this is why many people believe reballing works, when infact its just the heat.

 

That will likely die again within a year.

 

Still , its a cool thing to watch.

Re-balling does work And it is not the heat that fixes it. If the silicon is bad, it s done, there is no coming back. Reflowing the interposer board and re-balling however can revive BGA's that have limited signs of life or intermittent issues. Re-balling will not fix issues like a lifted pad or broken trace/de-laminated via on the main board however. If you re-ball a bga and have the same issue later, its not the heat "temporarily" fixing it, its that you didn't do the job right to begin with.

[mariushm]

 

Some faults are due to bad solder balls.

However, some faults are the actually detached gold bonding wires between the chip and the substrate that has the copper pads on which balls are placed. It just happens that when you heat the chip to apply the new solder balls, the internals also heat enough that those bonding wires sometimes get reattached.

 

There's also cases like what nVidia experienced, where they made a bad choice when it comes to substrate soldering ... most of their 65nm and 55nm chips were flawed and reballing would only help temporarily as the flaws manifested due to solder fatigue (heating and cooling cycles) - so you reball the chips and they may work for a few weeks until enough power on and power off (heat up, cool down) accumulate and internal solder fatigues / breaks down again

See https://www.theinquirer.net/inquirer/news/1004378/why-nvidia-chips-defective

or https://techreport.com/news/15720/chip-failures-nvidia-responds-at-last

 

This is one of the reasons Apple no longer works with nVidia - because nVidia refused to help them pay for a part of the repairs and replacements of the nVidia cards dying in laptops and various apple products. The Apple management got so pissed off on nVidia that they "blacklisted" them, they're now even refusing to accept new nVidia drivers in their operating systems, so new nVidia cards don't work well on Apple. See https://appleinsider.com/articles/19/01/18/apples-management-doesnt-want-nvidia-support-in-macos-and-thats-a-bad-sign-for-the-mac-pro

 

Onkyo also had a lot of issues with a DSP chip from TI, then with a HDMI mixer chip and then a network chip  ... reflowing or reballing the DSP chip would help for brief periods of time, making the unit work only to have it fail again within a year... it was an internal flaw of the chip

See https://www.avsforum.com/forum/90-receivers-amps-processors/1652514-onkyo-acknowledges-failed-units-extending-warrranties-until-2018-a.html