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Logic Board component fell off during screen repair

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During a screen repair I had a very small component fall off right below the rightmost screw of the dock connector. It is square and appears to have 4 solder pads on it. I'm not 100% sure this is actually the correct component as I just ended up with the tiny part on my sheet after I was all done so I had to go back in and look on the logic board for missing parts.

I was wondering A) what this is as I can't even read the part number it's so small, B) is it important, and C) how can I possibly reconnect it? Thanks for your help!

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mindseye11, that is reference designator U18_RF which is a 74AUP1G08GF INPUT AND GATE in a SOT891 package. It is available right here. Here is the datasheet. It is part of the Baseband circuitry. For a repair, it will need to be soldered back on. Hope this helps, good luck

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Thanks oldturkey, would this affect the cellular signal? So far that's the only thing I've found not working since I turned it on.

Do you have any tips on soldering something so small? Also, since the pads are on the back, how do I even get solder on there and stick it to the board at the same time? I've never solder something that didn't have legs on its sides.

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It's done via reflow method, can't use a soldering iron for that one. Yes it could affect the cell signal.

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Would that be done with a heat gun? Just use tweezers to hold the component in place and let the heat gun melt the existing solder back onto the board?

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that is in principle correct. Just don't burn the part, you will have to have good temp control and it will only take seconds.

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I'm looking a little closer at the component and it appears to only have 4 pads, while the logic board shows 6 pads. Is that right? The link you sent shows a component with 6 pads. Could the pads have come off? Is that salvageable?

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mindseye11 will be eternally grateful.
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