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.

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Knocked some tiny chips off, tips on what they are?

Hi all, I've been having a go at fixing my sisters iPhone 5s that she drowned and probably tried to turn on but its dead..

So far I gave the board a full Isopropyl bath, and desoldered the EMI shields and cleaned all under them, however in the process I knocked a few capacitors(?) off near the 3 screen connecters on the board, its now a total of 4 since I had to remove another 2 to re-tin the contacts.

So now my problem is how to reattach them to the board?

Consider that the smd's are under 1mm, so even my smallest chisel tip can't do it.

Thanks in advance, Seb

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EDIT: You can't see from the picture but the 2 smd chips on the right hand side are actually still attached, its the other 4 that aren't.

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Seb Stobbe, all the components you knocked off are part of the WLAN/BT circuitry. No exotic SMD components, just resistors and capacitors. Unless you know how to microsolder, there is no easy way to reattach them. If you do not have the tools, I would suggest that you find someone that may help you. You could contact this user and see if it can be fixed for a reasonable cost.

Reference designator R17_RF 0.00 1/32W resistor in a 01005 package (used as jumper)

Reference designator C105_RF 0.01UF 6.3V 10% capacitor in a 01005 package

Reference designator C37_RF 27PF 16V 5% capacitor in a 01005 package

Reference designator R14_RF 10K 5% 1/32W resistor in a 01005 package

Reference designator R16_RF 10K 5% 1/32W resistor in a 01005 package

Reference designator R15_RF 10K 5% 1/32W resistor in a 01005 package

Hope this helps, good luck.

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Thanks so much!

I have hakko 936 and 858d clones (Soldering and hot air) and I do have a chisel tip maybe 1 or 2mm longer than those 01005's, so the only equipment I might need would be a more liquid flux which I could make(?) and smaller diameter solder.

How do you know which resistors and sizes go in which place?

And now that I have removed 4, how would I identify which ones go where?

What is the difference between R 14, 15, 16?

What is the correct terminology for these "tiny" resistors and caps?

What kind of magnification would be most appropriate, I have looked for some glasses/goggles that pro watchmakers etc use but I can't find any for hobbyist grade (ie low budget, I will try to avoid microsoldering at least anything like 01005 size)

Thanks again for your answers :)

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R14_RF, R15_RF and R16_RF are the same value. R17_RF is a 0 K resistor and is most likely used as a jumper (pretty common use for a 0K value) As for where do they go, that is why I attached the image. Since you removed them, I hope you have them packaged and stored so that you know which component goes where. Unless you use smart smart tweezers or similar, there is no way to determine which goes where just by looking at it. To solder, the best would be some hot tweezers, but it can be done with a soldering iron (plenty of practice) For the magnification, that will depend on yourself. I use a USB microscope for some of my work, for others a simple magnifying headset will work. The terminology I used in my answer is the terminology to use. Not exactly sure what you are asking about that.

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Okay so the R value is the board location! I meant how do "you" know where everything goes and the values?

USB microscope is a good call, I'll look into it!

By terminology I meant are they SMD, but being surface mount they obviously are.. and the package sizes I stumbled across in the last hour, 01005 is imperial sized aka 0402! Can you tell I'm new to this stuff?!

How do I go about checking which chip is which?

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Nope, the R value denotes a Resistor whereas a C would be a Capacitor, a D a Diode and so forth. The value for a resistor is given as resistance in ohm. i.e. R14_Rf is strictly a designator for a particular resistor in a particular location. It does not tell you what the values of the resistor are. In your case R14_Rf is a 10K 5% 1/32W. that means it is a 10,000ohm resistor with a tolerance of 5% (+/-500ohm) and the 1/32Watt is the maximum power rating they can dissipate. Remember Ohm's Law:-)? Apple paints all their logicboard so that you will not know what is what unless you have a schematic.

You are of course right, they are all surface mount (versus through a hole). You can not tell which is which component by the package. For that you would need something to measure and identify each component. I use a pair of smart tweezers ( ST5-S Colibri) but there are cheaper ones on ebay/amazon etc. It is an invaluable tool and a must have when dealing with SMC

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OK got it! The number is what I was referring to as "the r value", my way with words is awful clearly!

How does one obtain a schematic, other than measuring every point on the board?

In the case of the tweezers, thanks!

Might I have broken any of the chips when removing or reattaching them, through heat?

Any further advice or equipment for soldering the 01005 size?

Thanks again!

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Hi Seb,

It sounds like you've gotten some good advice here. I would only add a suggestion that you first measure across the + and - battery pins to see if there is a full short somewhere on this board. If so, you'll need to identify and remove the short before any of this work would even matter.

This phone should be able to turn on and function pretty well in many ways without any of these components.

In a normal phone, you should measure very high resistance, aka "1", across the battery connector. If you have a beep at continuity testing, or very low resistance then you have bigger fish to fry with this phone. You'd need to see if you can find the source of the shorted component and replace it.

A donor board comes in very handy for this type of work---if you can find one that is the same phone but perhaps a victim of some other problem than water damage, you may find it more economical than attempting to buy each potential component individually.

best of luck

jessa

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Yeah there is non-infinite resistance across the top and bottom of battery connector on the board..

Any idea how I might go about checking for shorted components, or is it 'measure everything on the board'?

Thanks!

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A good start is to look for the worst of the oxidation on the board and start there. In order to do this work you really need the schematic--commonly available with a google search.

Another school of thought on short detection is that a short will declare itself via heat. You'd need to invest in a DC power supply and apply a voltage at the battery connect and see if you can detect where the board is heating up. Add in freezing spray and this can sometimes point you in the right directions. Often, you'll just see the power management ic heating up, but the actual short is in a cap somewhere nearby. If you find the damaged component and take it off, the short will resolve---unless you have multiple shorts ;)

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Seb Stobbe will be eternally grateful.
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