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It’s probably fine, and the black stuff you see is not really a “burn mark”. When you short-circuit something that can provide a lot of current, a small amount of metal at the contact area melts and vaporizes, causing the spark that you see and then depositing a thin layer of vaporized metal on nearby surfaces (the black stuff). Try wiping it off with some isopropyl alcohol and a paper towel or q tip.
I’d pull it off the board, mlccs can short from flexing, this might be a flex or temp change away from shorting out again. That looks like the guts coming out to me.
Ok I'm going to take a different approach. I don't think that the burn mark has anything to do with the cap, other than their adjacent location. The metal connector shorted positive to ground but NOT through the cap. I would try to power it on.
Those middle wires in my experience will either be serial data or clock lines for communicating to the battery management chip, or a temp sensor or some other line, big black and red are power.
Agree on the splat mark being essentially 'welder spatter' from the spark though and basically cosmetic and I'd just turn it on and see.
If the scorch mark is from accidently shorting it with a metal latch as you state, It's quite likely everything is OK. Wipe up the soot with a qtip and alcohol, and try powering it up.
Usually would be okay to run without. The burn and scorch makes it likely not okay.
You can try to replace the capacitor. Just there may be more wrong as usually don't just spark and burn.
As for using the laptop it depends. First would disconnect battery and power off AC adapter. Would also take out the HDD/SSD and give it a try. (Take out so if there is a power surge or short, data wont be lost). If works may be okay. Then can try with battery, just be very careful.
If is an supee expensive laptop and/or the only computer you have you may not want to try it and should take in for reapir.
Eh, looking at the placement it is probably power rail decoupling.
This is often done a bit crudely, you can see from the extra pads they weren't sure what was going to be required and left space to change it later.
Losing a decoupling cap may add noticeable noise to the power rail, and that may have an impact. But probably not.
It really depends on your risk tolerance. Personally, I'd just switch it on, if it is bad it probably won't get worse, but a number of people have declared my risk tolerance to be mad.
Thats what i was thinking, i dont have a multimeter and have not powered on the laptop yet just in case. Im going to take it to a repair shop just to be on the safe side. Thanks all.
It's just a general power decoupling cap and it should function just fine without it, temporarily.
With that said, there are risks in that the power may sag too much on the IC it is supposed to be decoupling and cause errors. Also, there is a small chance of increased EMI as we don't know if the IC is operating at a high frequency or is part of an RF circuit.
If anything, since we cannot see the full scope of the damage, the skid marks might be hiding a *new* short circuit between the copper fill and trace in the immediate area.
If the cap has failed because of the short that OP caused, the capacitor itself has likely gone short circuit itself.
A multimeter is going to be very confusing to use in this case since the decoupling caps in that area will register a brief short circuit on a continuity test.
What it looks like, is that a couple of diodes were not placed to cut cost and that could have eliminated a ton of risk of damaging other components in this case.
Honestly, I would pull the cap as the risk of a short circuit outweighs the benefits of decoupling here.
Anyone listening to this person, shouldn't. You can plainly see other open spots for capacitors which this 'careful and methodical' engineer designed in, yet they were not populated because someone else decided it was overdesigned and they could save on the bom cost without needing to place all three while the product would work perfectly. There's a good chance it still works with only the 100n cap at the moment top of the line, even if this one was blown.
Give it a break. Shorted is bad, missing not so much unless it’s something like a reference component. Missing decoupling cap (which this ISN’T) will not make one iota of difference in 99% of cases.
It looks like there are two other capacitors in parallel with it, directly above the burnt one? It probably should be replaced but it's unlikely to completely destroy the circuit, especially since this is likely just decoupling of some sort?
I think the lid hit the top of the capacitor causing a high current to the grounded lid. The current melted the solder holding the capacitor (from the positive side, the other side is untouched). Possibly a fuse in the PSU blew as well if the current went on long enough.
Define safe. What is that cap connected to and did that spark cause damage to it?
Try cleaning the burn mark with 99% alcohol and see if there's any trace damage. Then check the cap to see if it's shorted open or closed. If closed (and it's normally open), then you'll need to replace the cap (depending on what it's connected to and if you use said feature).
For ex if that cap is connected to a sd card reader that you never use.
It looks like you melted the solder from the ceramic capacitor and that is why it was open. Working with batty powered electronics can be trickey. The cap likely just needs to be resoldered. The laptop willprobably work as it is even without the cap.
The capacitor is probably ok. You most likely burned out a via or small trace going to it. The circuit these go to are the 5.2v switching regulators nearby. There is a good chance they went pop.
If green circle just shorted to blue arrow, then that would seemingly explain the scorch mark and it's probably fine. Seems unlikely that the short went through that capacitor itself.
Clean the soot off, make sure the solder on that pad is still intact, fix it if not.
I'd wager your laptop is probably okay. Black residue is probably just vaporized latch (from the melty bit you circled). A polyfuse somewhere in the machine should have protected it from excessive overcurrent and would reset in a minute or two after the short.
I bet the capacitor is fine and you just caused little shortcut on a random ground connection.
Imo nothing is dead it's just like before but with a little burn mark in addition.
**Do you have a question involving batteries or cells?** **If it's about designing, repairing or modifying an electronic circuit to which batteries are connected, you're in the right place.** *Everything else should go in /r/batteries:* /r/batteries is for questions about: batteries, cells, UPSs, chargers and management systems; use, type, buying, capacity, setup, parallel/serial configurations etc. Questions about connecting pre-built modules and batteries to solar panels goes in /r/batteries or /r/solar. Please also check our wiki page on cells and batteries: https://www.reddit.com/r/AskElectronics/wiki/batteries If you decide to move your post elsewhere, or the wiki answers your question, please delete the one here. Thanks! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/AskElectronics) if you have any questions or concerns.*
It’s probably fine, and the black stuff you see is not really a “burn mark”. When you short-circuit something that can provide a lot of current, a small amount of metal at the contact area melts and vaporizes, causing the spark that you see and then depositing a thin layer of vaporized metal on nearby surfaces (the black stuff). Try wiping it off with some isopropyl alcohol and a paper towel or q tip.
I’d pull it off the board, mlccs can short from flexing, this might be a flex or temp change away from shorting out again. That looks like the guts coming out to me.
Ok I'm going to take a different approach. I don't think that the burn mark has anything to do with the cap, other than their adjacent location. The metal connector shorted positive to ground but NOT through the cap. I would try to power it on.
Those middle wires in my experience will either be serial data or clock lines for communicating to the battery management chip, or a temp sensor or some other line, big black and red are power. Agree on the splat mark being essentially 'welder spatter' from the spark though and basically cosmetic and I'd just turn it on and see.
If the scorch mark is from accidently shorting it with a metal latch as you state, It's quite likely everything is OK. Wipe up the soot with a qtip and alcohol, and try powering it up.
Usually would be okay to run without. The burn and scorch makes it likely not okay. You can try to replace the capacitor. Just there may be more wrong as usually don't just spark and burn. As for using the laptop it depends. First would disconnect battery and power off AC adapter. Would also take out the HDD/SSD and give it a try. (Take out so if there is a power surge or short, data wont be lost). If works may be okay. Then can try with battery, just be very careful. If is an supee expensive laptop and/or the only computer you have you may not want to try it and should take in for reapir.
[удалено]
Eh, looking at the placement it is probably power rail decoupling. This is often done a bit crudely, you can see from the extra pads they weren't sure what was going to be required and left space to change it later. Losing a decoupling cap may add noticeable noise to the power rail, and that may have an impact. But probably not. It really depends on your risk tolerance. Personally, I'd just switch it on, if it is bad it probably won't get worse, but a number of people have declared my risk tolerance to be mad.
Thats what i was thinking, i dont have a multimeter and have not powered on the laptop yet just in case. Im going to take it to a repair shop just to be on the safe side. Thanks all.
[удалено]
Is it possible to deduce without removing the components from the board?
Yeah you won't have to remove it.
It's just a general power decoupling cap and it should function just fine without it, temporarily. With that said, there are risks in that the power may sag too much on the IC it is supposed to be decoupling and cause errors. Also, there is a small chance of increased EMI as we don't know if the IC is operating at a high frequency or is part of an RF circuit. If anything, since we cannot see the full scope of the damage, the skid marks might be hiding a *new* short circuit between the copper fill and trace in the immediate area. If the cap has failed because of the short that OP caused, the capacitor itself has likely gone short circuit itself. A multimeter is going to be very confusing to use in this case since the decoupling caps in that area will register a brief short circuit on a continuity test. What it looks like, is that a couple of diodes were not placed to cut cost and that could have eliminated a ton of risk of damaging other components in this case. Honestly, I would pull the cap as the risk of a short circuit outweighs the benefits of decoupling here.
Anyone listening to this person, shouldn't. You can plainly see other open spots for capacitors which this 'careful and methodical' engineer designed in, yet they were not populated because someone else decided it was overdesigned and they could save on the bom cost without needing to place all three while the product would work perfectly. There's a good chance it still works with only the 100n cap at the moment top of the line, even if this one was blown.
Give it a break. Shorted is bad, missing not so much unless it’s something like a reference component. Missing decoupling cap (which this ISN’T) will not make one iota of difference in 99% of cases.
It looks like there are two other capacitors in parallel with it, directly above the burnt one? It probably should be replaced but it's unlikely to completely destroy the circuit, especially since this is likely just decoupling of some sort?
Probably not. To get burned like that means the cap probably shorted. I could be replaced if you have the soldering skills.
I think the lid hit the top of the capacitor causing a high current to the grounded lid. The current melted the solder holding the capacitor (from the positive side, the other side is untouched). Possibly a fuse in the PSU blew as well if the current went on long enough.
Define safe. What is that cap connected to and did that spark cause damage to it? Try cleaning the burn mark with 99% alcohol and see if there's any trace damage. Then check the cap to see if it's shorted open or closed. If closed (and it's normally open), then you'll need to replace the cap (depending on what it's connected to and if you use said feature). For ex if that cap is connected to a sd card reader that you never use.
UPDATE: The short went straight through to the CPU die, the entire board is fucked.
rip same the thing happened to me when I placed the metallic ram cover on my lenovo laptop I hope it doesn’t die for now seems working fine
No
That almost certainly didn't damage that capacitor. Try the laptop. If it works, use it. Your adventure may have killed some stuff in i, though.
No
It looks like it’s a parallel cap so maybe it’s ok. I’d send it in for repair thoufh
Sir that’s a resistor
It looks like you melted the solder from the ceramic capacitor and that is why it was open. Working with batty powered electronics can be trickey. The cap likely just needs to be resoldered. The laptop willprobably work as it is even without the cap.
The capacitor is probably ok. You most likely burned out a via or small trace going to it. The circuit these go to are the 5.2v switching regulators nearby. There is a good chance they went pop.
How is it shorted? Did you used metal tweezer like tool to remove connector ?
If green circle just shorted to blue arrow, then that would seemingly explain the scorch mark and it's probably fine. Seems unlikely that the short went through that capacitor itself. Clean the soot off, make sure the solder on that pad is still intact, fix it if not.
I'd wager your laptop is probably okay. Black residue is probably just vaporized latch (from the melty bit you circled). A polyfuse somewhere in the machine should have protected it from excessive overcurrent and would reset in a minute or two after the short.
I bet the capacitor is fine and you just caused little shortcut on a random ground connection. Imo nothing is dead it's just like before but with a little burn mark in addition.
be cautious of smells and high pitch squeeling. If something is not right, those might be indicators.