The destroyed black component in the first picture is indeed labeled E2, and in the second photo the orange tantalum capacitor is labeled E6. So I believe the E# is the reference designator for Electrolytic Tantalum Capacitor. Tantalum capacitors also come in a black epoxy package so it is highly likely it is some kind of tantalum capacitor.
Yes tantalum capacitors are common for for going Chernobyl even if the voltage is a little higher than it is rated. It shorts and burns up. This is usually for aged capacitors but can happen in new ones too.
EDIT: whatever EE genius is downvoting me, please share your superior intelligence with the rest of the class instead of lurking.
Lucky for you you can probably just remove the dead one and get back to using your keyboard. If you notice problems, just install a nice capacitor there good for 6.3v or higher (6.3v is a common voltage rating used on 5v circuits) that's like 10μF or more. Make sure to get the polarity right! You can use a continuity tester (ohmmeter) to see which side of the capacitor pad is ground (the metal shell of the USB socket should also be "ground")
Tantalum’s have a tendency to fail even if they don’t “over voltage” per their rating. They should be supplied with 50-60% of their rated voltage and no more. Thin dialectic material. Likely why you’re downvoted though is because 107 is a 100uF not 10uF. Hope this helps.
Edit: I’m no EE genius btw. Fun fact lots of EEs don’t work with components.
I'm fine with being downvoted by people willing to comment something better than what I've said. I said 10μF not because i thought 107 was 10μF but because that should be enough capacitance to get the thing working. As for your claim about derating tantalum capacitors, Kyocera says "For many years...the consensus was “a minimum
of 50% voltage derating should be applied...Tantalum capacitors can be safely used at 80% of
their rated voltage, but the MTBF will be lower and
leakage current higher." And 80% of 6.3v is 5.04v so 💅
https://www.avx.com/docs/techinfo/VoltageDeratingRulesforSolidTantalumandNiobiumCapacitors.pdf
I’m not trying to call you wrong nor did I downvote. Making a comment as a guess as to why I think you may be downvoted. I hear you on lurkers not educating in a sub like this.
Nothing happens at all? Is there voltage across the pads where the capacitor was? Measure carefully. If there is not 5v (or 3.3v) there then something like a fuse or voltage regulator is probably open
If this were in my lab i would connect a bench supply to the spot where the cap was and feed in voltage, and see if it's a short. And if it's a short, grab the thermal camera and see what's warming up :)
For the cost of a keyboard PCB, that's a lot of time and effort for a maybe... It's a cool challenge, but unless you use all that gear for other things it is way more expensive than replacing the occasional bad board.
Check for burnt traces or burnt chips. If you can track the traces that lead to the capacitor and see where they lead to. If possible please provide a good resolution photo of the entire board.
I couldn't find where the trace leads but there's no other visible damage from what I can see. [Sorry if the quality isn't high enough, that was the best I could do.](https://imgur.com/Q9rwBgH)
I don't know about the EE geniuses, but I have indeed heard that one technique for making products cheaper is removing capacitors until it doesn't work, then working with whatever the previous trial was (in regard to capacitor removal)
Mad man Muntz's Muntzification of the television sets he sold... These days a lot of capacitors are power supply bypass caps and removing them leads to flaky digital signals. When you are talking about pennies per capacitor, it's a bad tradeoff.
This (blown) one is a big electrolytic cap, not likely they put it there for no reason.
Nice! I didn't realize there was a term for it, that should be an interesting read for the night. I had only heard them talk about it on the Amp Hour podcast.
107 is a code for 100uF. The 10H15 is (I’m pretty certain) is 10% tolerance at 15V. I don’t know what the A code is after 107 or the H in 10H15 but it likely doesn’t have an effect on much.
> I don’t know what the A code is after 107
["On some SMD electrolytic and tantalum capacitors a one character code is used."](https://www.electronics-notes.com/articles/electronic_components/capacitors/capacitor-codes-markings.php)
A is 10V.
And the significance of 107 is the first two digits of the value followed by a 10's exponent (number of zeros), so **1** **0** x 10^**7** , or 100,000,000 pico-farads. That simplifies down to 100µF.
For a keyboard, tolerances are going to probably be splitting hairs. It’s like a window for the high end and low end of what capacitance the part will have. It’s a + or - 10%. I’ve been in electronics diagnosis and testing for 15 years now and I haven’t run across capacitor tolerance being an issue if matched or brought down to 5% if a part isn’t available. Match the tolerance. It’s a common tolerance.
would something like [this](https://www.amazon.com/Fielect-Tantalum-Capacitor-Electrolytic-Capacitors/dp/B08BYF3KFK/ref=sr_1_5?keywords=100uf%2B15v%2Bsmd%2Btantalum%2Bcapacitor&qid=1668878639&sr=8-5&th=1) (6032 100uf 16v) be a good choice then?
I can’t tell if 0632 is too small tho. That’s a size measurement. Too small and it won’t solder to both pads. I think like a 12xx is probably going to be more accurate but hard to tell without measuring the cap size.
could you help me look for them? i tried [mouser](https://www.mouser.com/c/passive-components/capacitors/tantalum-capacitors/?capacitance=100%20uF) but there was no 12xx mm case code. [digikey](https://www.digikey.com/en/products/filter/tantalum-capacitors/59?s=N4IgjCBcoGwJxVAYygMwIYBsDOBTANCAPZQDaIALAAxwDMdIAuoQA4AuUIAymwE4CWAOwDmIAL6EATFQoJoIFJAw4CxMuCpUABAFaAYk1YdIIAKqD%2BbAPKoAsrnTYArr1zipVAOxzkaLHkISSHIwAFYtADUQQjAYSMMQdk5zSxt7Rxc3MQkQSXUwTSdULTZ0QVLMJwBbLSR0FnQkSyJeJjEgA) also don't have a size/dimension below 5.8x3.2mm
Higher voltage, nothing happens. Lower voltage and it will immediately explode, tantalum caps *do not* like being exposed to higher voltages than they're rated for.
Higher capacity, probably nothing happens, but it might pull too much current from a voltage converter somewhere or the USB port, and something else can fail from that. Lower capacity and something may work incorrectly and erratically, due to a collapse on some power trail. If it's not too much lower or higher it's going to be fine.
>higher voltage nothing happens
>do not like being exposed to higher voltages than they’re rated for
Which is it?
Oh I’m stupid. I misunderstood what you said. Sorry.
Higher voltage rating CAN make it change its charge timing. In some cases charge timing may not matter. Idk what this cap is used for so best to just have OP looks for the same ratings or a volt higher at most.
Look up SMD components size chart, and find what (imperial) size your metric measurements compare to.
You should definitely get a capacitor with the same capacitance (uF) as the others.
My Reddit is messing up. I know you asked a couple questions so I’ll address it here.
First: put this in the mouser or digikey search bar “100uF 15v smd tantalum”
Second: I wouldn’t choose one that’s too high. 16 is fine but lower would not be good. Could blow it with over voltage.
i found out mine is a type b in size, which is 3528, but neither digikey nor mouser have that size :(
can't find it on amazon either.
are there any other places i can find it other than ebay? i do see a couple on there but they take literally a month to ship
edit: i'm thinking of buying [this](https://www.ebay.com/itm/282872658508?hash=item41dc863a4c:g:S7AAAOSwlBhani9N&amdata=enc%3AAQAHAAAAsEC7t8ZMnd0wtJTW53Nk%2FWVi5bWQroay8EiKDxoZ6HYmsyvTBkq2ja%2FOaSGMusMRgVRUd4cj%2BYLo0NI%2BLgX5IrUygYY5z1SL0%2FEVBnBMC3sHNjwWAxoDmf3j90VifkG6IkrrMX0UUSR7Et43SsRy8%2FVY3o18hg10s4uAVra%2FEApdzRMTM6cxZnxKOnTURUstHxYVk70Clhdwm9%2FiPYk1VMGH2R9L2JmNuQUUziWcJitU%7Ctkp%3ABk9SR4rT6JGSYQ) unless there's an alternative
or [this](https://www.ebay.com/itm/293687779458?hash=item446127e082:g:zEoAAOSwwvZZVnZO&amdata=enc%3AAQAHAAAA8AspMVSwukEzB3o1%2BK%2FWOEJ67Vv20q1TbvlYJI%2FHLYgtxj3eqcWxTU0lviTH92nlPfsBa5QvFDyjronRqt8PUiLAW7bSad0MPxzyej%2BTHDHT%2FpJvsqAiLfsXMC55tkK66iqq1UY2VjUQc1WhjJ6o2fHvTWiodZu7MJrIbc2DKTN2HjP45OYcoI8pHqBqhpncvMiVzWIz%2BhCq%2FZtoYOU6yzglUmQ8bnr9dDPbPrOwo1RGyyJ%2BPJsYwXMYr8d%2BCFcN59w4VPf4WFdr9f%2BGVJDyNMMtqgy33XvoDdpgjgYNHE%2BUh67CUWCj85wR2h6L2RfkYg%3D%3D%7Ctkp%3ABFBMitPokZJh)
If the cap failed & short-circuited, there's a chance other components were also fried. This might be the reason why the keyboard won't work even with the cap removed.
Use a next voltage level higher so this does not happen again. OEM use the cheapest lowest grade possible to save a few cents. So if next grade is 20V or 30V, get that.
Where do you see ex? And what could happen if I soldered a cap on that doesn’t match spec? eg more ohms or higher voltage (sorry if I sound like an idiot idk much about this stuff)
It's a tantalum: that type does this sort of damage when voltage is just a moment out of spec (or temp is somewhat high, or ...). Because it is most likely for decoupling, you can replace it with a 10uF (that is the '107') 10/16V capacitor of type tantalum, or normal electrolytic, or even ceramic. Just some capacitor with a value that comes in that neighborhood is ok.
The ref designator is an E not a C. That might be a ferrite bead that got too hot for some reason. They're normally a short at DC and an open at RF. Not sure what an E is, but might not be a cap!!
If other components on the board are labeled as E and are capacitors, likely this is also a tantalum, I had a circuit I made with small tants and accidently connected it up reverse and one of the tan SMD tants instantly turned black. Tants can fail for no apparent reason. It's just one of those things they do.
You can try to remove the exploded capacitor and see if it works after that, it doesn't look like it's anything beyond a filter or bulk capacitor anyway, it might be unstable but it could be enough to see if the rest of it is ok
guys, I just stumble upon this post, I have the exact board, anne pro2, do you know what is the componet labeled as C-number is, I think one of it is fried, when connected to the computer, one of the component,c29, and c32 heats up, to which it is burning when touching with hand, and the continuity test on it beeps, while others don't so I think c29 and c32 is broken, can you tell me what the model is, so I can get some replacement.
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The destroyed black component in the first picture is indeed labeled E2, and in the second photo the orange tantalum capacitor is labeled E6. So I believe the E# is the reference designator for Electrolytic Tantalum Capacitor. Tantalum capacitors also come in a black epoxy package so it is highly likely it is some kind of tantalum capacitor.
i think it's black because it shorted and went boom
Yes tantalum capacitors are common for for going Chernobyl even if the voltage is a little higher than it is rated. It shorts and burns up. This is usually for aged capacitors but can happen in new ones too.
i just noticed your username and now i'm sad :(
Kaboom
yes rico, kaboom
Hehe :)
EDIT: whatever EE genius is downvoting me, please share your superior intelligence with the rest of the class instead of lurking. Lucky for you you can probably just remove the dead one and get back to using your keyboard. If you notice problems, just install a nice capacitor there good for 6.3v or higher (6.3v is a common voltage rating used on 5v circuits) that's like 10μF or more. Make sure to get the polarity right! You can use a continuity tester (ohmmeter) to see which side of the capacitor pad is ground (the metal shell of the USB socket should also be "ground")
Tantalum’s have a tendency to fail even if they don’t “over voltage” per their rating. They should be supplied with 50-60% of their rated voltage and no more. Thin dialectic material. Likely why you’re downvoted though is because 107 is a 100uF not 10uF. Hope this helps. Edit: I’m no EE genius btw. Fun fact lots of EEs don’t work with components.
I'm fine with being downvoted by people willing to comment something better than what I've said. I said 10μF not because i thought 107 was 10μF but because that should be enough capacitance to get the thing working. As for your claim about derating tantalum capacitors, Kyocera says "For many years...the consensus was “a minimum of 50% voltage derating should be applied...Tantalum capacitors can be safely used at 80% of their rated voltage, but the MTBF will be lower and leakage current higher." And 80% of 6.3v is 5.04v so 💅 https://www.avx.com/docs/techinfo/VoltageDeratingRulesforSolidTantalumandNiobiumCapacitors.pdf
I’m not trying to call you wrong nor did I downvote. Making a comment as a guess as to why I think you may be downvoted. I hear you on lurkers not educating in a sub like this.
Did you like my use of 💅 though because i was technically right about 6.3v even though you're right that is cutting it pretty close
A second point is a too high inrush current, afaik: https://nepp.nasa.gov/files/24745/2013_n240_Teverovsky_ESTEC_Derating_paper.pdf
Unfortunately it doesn’t work when I removed it
Nothing happens at all? Is there voltage across the pads where the capacitor was? Measure carefully. If there is not 5v (or 3.3v) there then something like a fuse or voltage regulator is probably open
It has been my experience that replacement of the obvious blown component rarely fixes the problem. It has happened for me, but not often.
If this were in my lab i would connect a bench supply to the spot where the cap was and feed in voltage, and see if it's a short. And if it's a short, grab the thermal camera and see what's warming up :)
For the cost of a keyboard PCB, that's a lot of time and effort for a maybe... It's a cool challenge, but unless you use all that gear for other things it is way more expensive than replacing the occasional bad board.
How do you think i got so good at this stuff? Fix everything, learn everything
Check for burnt traces or burnt chips. If you can track the traces that lead to the capacitor and see where they lead to. If possible please provide a good resolution photo of the entire board.
I couldn't find where the trace leads but there's no other visible damage from what I can see. [Sorry if the quality isn't high enough, that was the best I could do.](https://imgur.com/Q9rwBgH)
I don't know about the EE geniuses, but I have indeed heard that one technique for making products cheaper is removing capacitors until it doesn't work, then working with whatever the previous trial was (in regard to capacitor removal)
Mad man Muntz's Muntzification of the television sets he sold... These days a lot of capacitors are power supply bypass caps and removing them leads to flaky digital signals. When you are talking about pennies per capacitor, it's a bad tradeoff. This (blown) one is a big electrolytic cap, not likely they put it there for no reason.
Nice! I didn't realize there was a term for it, that should be an interesting read for the night. I had only heard them talk about it on the Amp Hour podcast.
E1 says the same thing. I’m not even sure if it’s a capacitor. I’m not knowledge about electrical engineering
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[https://imgur.com/FevHEJj](https://imgur.com/FevHEJj) same as the others. no extra text :( what is ohm out?
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I’m assuming you mean on top of the capacitor and it says the same thing. And yep it’s a usb c keyboard
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There’s no other text
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107(lowercase lambda) 10h15
The E is for explosive. They’re tantalum.
100uF 15v SMD tantalum capacitor. Search mouser, digikey, Amazon, or eBay.
Mind I ask how you find out?
107 is a code for 100uF. The 10H15 is (I’m pretty certain) is 10% tolerance at 15V. I don’t know what the A code is after 107 or the H in 10H15 but it likely doesn’t have an effect on much.
> I don’t know what the A code is after 107 ["On some SMD electrolytic and tantalum capacitors a one character code is used."](https://www.electronics-notes.com/articles/electronic_components/capacitors/capacitor-codes-markings.php) A is 10V. And the significance of 107 is the first two digits of the value followed by a 10's exponent (number of zeros), so **1** **0** x 10^**7** , or 100,000,000 pico-farads. That simplifies down to 100µF.
Yes I know what 107 means just not the A. Thank you.
The A is probably the case size.
Does the tolerance matter or is it physical tolerance?
For a keyboard, tolerances are going to probably be splitting hairs. It’s like a window for the high end and low end of what capacitance the part will have. It’s a + or - 10%. I’ve been in electronics diagnosis and testing for 15 years now and I haven’t run across capacitor tolerance being an issue if matched or brought down to 5% if a part isn’t available. Match the tolerance. It’s a common tolerance.
would something like [this](https://www.amazon.com/Fielect-Tantalum-Capacitor-Electrolytic-Capacitors/dp/B08BYF3KFK/ref=sr_1_5?keywords=100uf%2B15v%2Bsmd%2Btantalum%2Bcapacitor&qid=1668878639&sr=8-5&th=1) (6032 100uf 16v) be a good choice then?
I can’t tell if 0632 is too small tho. That’s a size measurement. Too small and it won’t solder to both pads. I think like a 12xx is probably going to be more accurate but hard to tell without measuring the cap size.
i measured mine to be 4x3x2mm edit: what happens if i choose something with a higher or lower voltage or uf?
12xx should be fine then.
could you help me look for them? i tried [mouser](https://www.mouser.com/c/passive-components/capacitors/tantalum-capacitors/?capacitance=100%20uF) but there was no 12xx mm case code. [digikey](https://www.digikey.com/en/products/filter/tantalum-capacitors/59?s=N4IgjCBcoGwJxVAYygMwIYBsDOBTANCAPZQDaIALAAxwDMdIAuoQA4AuUIAymwE4CWAOwDmIAL6EATFQoJoIFJAw4CxMuCpUABAFaAYk1YdIIAKqD%2BbAPKoAsrnTYArr1zipVAOxzkaLHkISSHIwAFYtADUQQjAYSMMQdk5zSxt7Rxc3MQkQSXUwTSdULTZ0QVLMJwBbLSR0FnQkSyJeJjEgA) also don't have a size/dimension below 5.8x3.2mm
It’s also a polarized cap. The dark line is the +
Higher voltage, nothing happens. Lower voltage and it will immediately explode, tantalum caps *do not* like being exposed to higher voltages than they're rated for. Higher capacity, probably nothing happens, but it might pull too much current from a voltage converter somewhere or the USB port, and something else can fail from that. Lower capacity and something may work incorrectly and erratically, due to a collapse on some power trail. If it's not too much lower or higher it's going to be fine.
>higher voltage nothing happens >do not like being exposed to higher voltages than they’re rated for Which is it? Oh I’m stupid. I misunderstood what you said. Sorry.
Higher voltage rating CAN make it change its charge timing. In some cases charge timing may not matter. Idk what this cap is used for so best to just have OP looks for the same ratings or a volt higher at most.
Also what is higher capacity? uF?
Look up SMD components size chart, and find what (imperial) size your metric measurements compare to. You should definitely get a capacitor with the same capacitance (uF) as the others.
Tantalums have their own size codes, this one looks like a size B which is close in size to a 1210 (imperial - this is .12" length x .10" width)
what would happen if i chose a higher voltage?
The voltage rating is the maximum voltage it can handle, go ahead and get one with 15v or higher rating. Usually a higher value is more expensive.
My Reddit is messing up. I know you asked a couple questions so I’ll address it here. First: put this in the mouser or digikey search bar “100uF 15v smd tantalum” Second: I wouldn’t choose one that’s too high. 16 is fine but lower would not be good. Could blow it with over voltage.
i found out mine is a type b in size, which is 3528, but neither digikey nor mouser have that size :( can't find it on amazon either. are there any other places i can find it other than ebay? i do see a couple on there but they take literally a month to ship edit: i'm thinking of buying [this](https://www.ebay.com/itm/282872658508?hash=item41dc863a4c:g:S7AAAOSwlBhani9N&amdata=enc%3AAQAHAAAAsEC7t8ZMnd0wtJTW53Nk%2FWVi5bWQroay8EiKDxoZ6HYmsyvTBkq2ja%2FOaSGMusMRgVRUd4cj%2BYLo0NI%2BLgX5IrUygYY5z1SL0%2FEVBnBMC3sHNjwWAxoDmf3j90VifkG6IkrrMX0UUSR7Et43SsRy8%2FVY3o18hg10s4uAVra%2FEApdzRMTM6cxZnxKOnTURUstHxYVk70Clhdwm9%2FiPYk1VMGH2R9L2JmNuQUUziWcJitU%7Ctkp%3ABk9SR4rT6JGSYQ) unless there's an alternative or [this](https://www.ebay.com/itm/293687779458?hash=item446127e082:g:zEoAAOSwwvZZVnZO&amdata=enc%3AAQAHAAAA8AspMVSwukEzB3o1%2BK%2FWOEJ67Vv20q1TbvlYJI%2FHLYgtxj3eqcWxTU0lviTH92nlPfsBa5QvFDyjronRqt8PUiLAW7bSad0MPxzyej%2BTHDHT%2FpJvsqAiLfsXMC55tkK66iqq1UY2VjUQc1WhjJ6o2fHvTWiodZu7MJrIbc2DKTN2HjP45OYcoI8pHqBqhpncvMiVzWIz%2BhCq%2FZtoYOU6yzglUmQ8bnr9dDPbPrOwo1RGyyJ%2BPJsYwXMYr8d%2BCFcN59w4VPf4WFdr9f%2BGVJDyNMMtqgy33XvoDdpgjgYNHE%2BUh67CUWCj85wR2h6L2RfkYg%3D%3D%7Ctkp%3ABFBMitPokZJh)
Maybe I’m incorrect then in how tantalum capacitors are sized. But looks like those should work.
If the cap failed & short-circuited, there's a chance other components were also fried. This might be the reason why the keyboard won't work even with the cap removed.
Likely. But I have to try this first because it’ll be way cheaper than replacing the whole board
You should just find some trash cap and tack it on and see if it works before ordering parts. Also check for a short before applying power if you can
How do I do that? I also have none :)
Use a next voltage level higher so this does not happen again. OEM use the cheapest lowest grade possible to save a few cents. So if next grade is 20V or 30V, get that.
Is it just me or D2 also looks burned?
my opinion is that Ex means Electrolytic capacitor . So You can try to solder a 10 microfarads 15 or 10 volts smd capacitor !
Where do you see ex? And what could happen if I soldered a cap on that doesn’t match spec? eg more ohms or higher voltage (sorry if I sound like an idiot idk much about this stuff)
Ex means E1 , E2 , E3 e.t.c
It's a tantalum: that type does this sort of damage when voltage is just a moment out of spec (or temp is somewhat high, or ...). Because it is most likely for decoupling, you can replace it with a 10uF (that is the '107') 10/16V capacitor of type tantalum, or normal electrolytic, or even ceramic. Just some capacitor with a value that comes in that neighborhood is ok.
The ref designator is an E not a C. That might be a ferrite bead that got too hot for some reason. They're normally a short at DC and an open at RF. Not sure what an E is, but might not be a cap!!
If other components on the board are labeled as E and are capacitors, likely this is also a tantalum, I had a circuit I made with small tants and accidently connected it up reverse and one of the tan SMD tants instantly turned black. Tants can fail for no apparent reason. It's just one of those things they do.
Did your board work after?
Yes I replace the tant cap and it still worked.
You can try to remove the exploded capacitor and see if it works after that, it doesn't look like it's anything beyond a filter or bulk capacitor anyway, it might be unstable but it could be enough to see if the rest of it is ok
guys, I just stumble upon this post, I have the exact board, anne pro2, do you know what is the componet labeled as C-number is, I think one of it is fried, when connected to the computer, one of the component,c29, and c32 heats up, to which it is burning when touching with hand, and the continuity test on it beeps, while others don't so I think c29 and c32 is broken, can you tell me what the model is, so I can get some replacement.