The Apple iPhone 5s was announced on September 10, 2013. Repair of this device is similar to the previous models, and requires screwdrivers and prying tools. Available as GSM or CDMA / 16, 32, or 64 GB / Silver, Gold, and Space Gray.

3129 Questions View all

U2 IC Charge chip replacement! Please help!

Hello again ifixit.

Im just learning how to do BGA work and micro soldering and such. I had a quick question of replacing the U2 IC on an iPhone 5s, how do you go about lining up the new chip? It doesn't seem to want to sit correctly on the board connections, it keeps sliding to the side when I go to heat it up and if I put pressure on it, it immediately slips. Is there someone to clean up the board connections after removing the old chip? I had tried using desoldering wick to clean them up, but on a board i have tried that on before, it ended up pulling a couple of the connections away from the board. And I don't want to do that as it seems impossible to get solder to form another connection in those spots now.

I guess basically what I'm asking is, how does one clean up the U2 IC connections after removal of the old chip, and then how does one line up the new chip without crossing connections? It seems in most instructional videos, they skip the part where the clean it up.

Any help is greatly appreciated!

Answer this question I have this problem too

Is this a good question?

Score 1
Add a comment

2 Answers

Most Helpful Answer

I have a complete U2 video that I'm editing now that details this. It will appear on the iPad rehab YT channel.

You use braid on the pads. And you let the chip align itself.

Was this answer helpful?

Score 2

Comments:

Please get that video up! There is no good english video about U2 replacement.

Align itself? That's interesting, but I can't seem to get that result. It always just slides to one side or turns slightly

by

If you get it close, it will align itself when you apply hot air. Try to keep your hot air source as perpendicular to the board as possible, and of course don't bring it in too fast or your chip will blow away and disappear into the 6th dimension.

by

So I assume I should use the lowest air speed setting? What temperature should the air be? I've been using 400F

by

It depends on your hot air system. Listen to the way the hot air whistles when it hits the board, that is a good indication of when you are starting to heat it up and solder it on.

by

Josh. It slides cos your air speed is too much. Adjust the minimum air pressure so you can easily solder that

by

Add a comment

Use flux and quality solder wick. Make sure your equipment is getting hot enough and maintaining temperature. What size tip are you using? You will damage the pads on the board by either physically scratching them off or not using enough heat and pulling them off with the wick or chip. Don't remove the wick without keeping adequate heat on it.

Was this answer helpful?

Score 1
Add a comment

Add your answer

Josh White will be eternally grateful.
View Statistics:

Past 24 Hours: 2

Past 7 Days: 19

Past 30 Days: 82

All Time: 2,238