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I apologize for asking 2 questions here. I 3D printed a case for the Pi Zero and it was a bit snug. I took it out of the case with a pair of needle nose pliers (stupid, I know) and a piece came off. The piece was soldered on, and extremely small. I booted it up to see if it still worked, and it did. I could try to solder it back on, but it's almost too small for me to do it personally.Should I try to solder it back on? Since it still turns on and runs, should I just not worry about it? enter image description here

  • Note that in this day and age the electronic industry in some parts of the world now really want everyone to use lead-free solder which is all well and good for health and safety of the people around when PWBs are soldered up but generally the solder that is used as a replacement does not "flow" quite so well as the older tin/lead-based and melts at a higher temperature! Close inspection of the image suggests the component knocked off is a supply decoupling capacitor for the Micro SD card - you may get away without it... – SlySven Jul 19 '16 at 23:45
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Set the piece in place and use a paper clip to hold it, then use a heat gun on low air setting to solder it in. It will take some time to get it to the right heat and do not bump the unit at all during and for 5 mins after.

Flat level stable surface and try to keep the heat off the rest of the board as much as you can.

Also since it is near the SD slot where there is likely plastic in it, use some form of shield on the side of that to deflect heat from the slot.

To answer the other question, it is likely a capacitor if it boots fine. I don't have a zero nor know where the schematics are off hand. But running it without the capacitor can be dangerous to the stability of the unit. Depending on what circuit it is for, you could "spike" voltage or have a voltage drop which depending on tolerances could fry other components.

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You can see the part in this picture. It is a ceramic capacitor. Most likely it is a decoupling capacitor which means it is used to help suppress voltage variations/spikes.

Your Pi0 may crash under particular types of workload. It's hard to say how exactly since I don't think there is a published schematic for the Pi0.

If it's not bothering you for your use cases, I would just leave it be.

Soldering it on shouldn't be too hard, but you should practise on some scrapped electronics first.

enter image description here

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Normally a piece does NOT come off. Removing a surface mounted component without the correct tools is almost impossible so it is more likely the capacitor is damaged. (Unwanted components are normally "removed" by crushing them.)

Do not attempt to reattach. Most electronic design uses a liberal sprinkling of decoupling capacitors - a missing item is unlikely to cause any problems.

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" (Unwanted components are normally "removed" by crushing them.)"...... i'm in the consumer electronics repair business, and i desolder the defective component, remove it with tweezers, and replace it. crushing the original component can rip up the copper pads (the solder wick can too if you aren't careful). in the case in question, the best method would be to wick the remaining solder, put a dot of solder on one pad, cover both pads with liquid flux, solder the new component to the pad wit a dot of solder on it, making sure the other end of the part sits flush on the other pad. after the solder on the first joint cools and hardens, solder the other end of the part, clean off the flux and it's done.
it takes some practice, and the temperature of the iron needs to be "just right" so you don't damage the pads with the solder wick from having the temp too hot and melting the glue outright, or too cold, requiring more time in contact with the pad, which gives the heat more time to loosen the glue. find an old dead DVD player or something to practice on first until you can remove and replace a component without damaging it or the board.

if the pi runs ok without the cap, then the capacitance value of it probably isn't critical, and you should be able to use a 0.1uf down to about 0.01uf to replace it.

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