need help identifying a capacitor

pendragon1

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Oct 7, 2000
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trying to repair a makerbot board that had this cap knocked off of it. for these things my google-fu is lacking, i think, searching and its coming back as nichicon 4.7uf 25v, but that doesnt seem right to me but could be but where does the 72A come in... help?!

WP_20221216_14_48_22_Pro.jpg

it did have a little black plastic base and is surface mount. its about 5mm across and 6mm tall...
 
Based on this link the 72A is likely a lot code: https://forum.digikey.com/t/smt-electrolytic-capacitor-with-no-voltage-rating/974
I did some parametric searching at Digi-Key at this link which would be a good starting point: https://www.digikey.com/short/vbq98djj
If you had a set of calipers you might be able to narrow down a replacement based on size.
If ESR or impedance are critical in this application you might be out of luck but in my experience a designer already has to assume an electrolytic will derate due to age so the design tolerance is quite wide.

Edit: It looks like a 47uF 25V capacitor.
 
Based on this link the 72A is likely a lot code: https://forum.digikey.com/t/smt-electrolytic-capacitor-with-no-voltage-rating/974
I did some parametric searching at Digi-Key at this link which would be a good starting point: https://www.digikey.com/short/vbq98djj
If you had a set of calipers you might be able to narrow down a replacement based on size.
If ESR or impedance are critical in this application you might be out of luck but in my experience a designer already has to assume an electrolytic will derate due to age so the design tolerance is quite wide.

Edit: It looks like a 47uF 25V capacitor.
i was starting to think the 72A was lot, didnt find anything else that fit. and yeah looking back at my search history the 4.7 was a typo, it should have been 47. so ill measure it properly and see what i can track down. i think i found it or a very close match on mouser, for a whopping $0.50.
ps thanks for the input!
 
47uF, 25V is what you've got there. 72A is the lot code.

Also heed the fact that this is an electrolytic cap, hence polarized. A quick check with your DVM will confirm which pad is ground, which is what I'd do to confirm which is which.
 
i was starting to think the 72A was lot, didnt find anything else that fit. and yeah looking back at my search history the 4.7 was a typo, it should have been 47. so ill measure it properly and see what i can track down. i think i found it or a very close match on mouser, for a whopping $0.50.
ps thanks for the input!

50 cents with $7 shipping. When ordering from Mouser, Digikey, etc. it's best to wait until you need a whole bunch of parts to offset the shipping cost.

If you don't care about aesthetics, you can use a normal radial leaded through hole cap on SMT pads. Just cut the legs short, bend them into opposing L shapes and solder them to the pads. I do this for testing to make sure a device works properly to warrant spending good money on caps you can only really use once. You can buy a whole bag of dodgy ebay capacitors for testing for a lot cheaper than a quality cap if you just need them around for emergency repairs or testing.

 
50 cents with $7 shipping. When ordering from Mouser, Digikey, etc. it's best to wait until you need a whole bunch of parts to offset the shipping cost.

If you don't care about aesthetics, you can use a normal radial leaded through hole cap on SMT pads. Just cut the legs short, bend them into opposing L shapes and solder them to the pads. I do this for testing to make sure a device works properly to warrant spending good money on caps you can only really use once. You can buy a whole bag of dodgy ebay capacitors for testing for a lot cheaper than a quality cap if you just need them around for emergency repairs or testing.


thanks for the tip but im not too worried about a few bucks for shipping. a new board is $350+, so $20 for a cap and the USB-b port thats needed isnt so bad.
 
so im finally getting around to this repair and realized i accidentally got 16v instead of 25v, not sure how... think theyre still usable?

edit: nm, i just ordered the right ones and theyll be here tomorrow. one more thing, "audio grade" doesnt matter right? just means theyre better in audio equip but can still use them normally right?
 
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so im finally getting around to this repair and realized i accidentally got 16v instead of 25v, not sure how... think theyre still usable?

edit: nm, i just ordered the right ones and theyll be here tomorrow. one more thing, "audio grade" doesnt matter right? just means theyre better in audio equip but can still use them normally right?

You don't want to go down a voltage level for capacitors, unless you really understand the circuit and you want to be sure it fails around the end of the warranty. It doesn't hurt to use a capacitor with a larger voltage rating though.

Audio grade should be fine either way. Might mean better tolerances or something?
 
You'll eventually find a use for the 16-Volt one also. I used to see them when I fixed some old computer screens.
It's usually better to buy a few more, as was suggested. Wrong continent, but the company I use starts lowering prices per unit even for like 3-5+ pieces of a $2 part.
I just wanted to include myself in the thread, I get excited when something gets fixed :D
Edit: audio caps are way overpriced.
Edit2: higher voltage caps often have slightly higher ESR (resistance) which has bearing on some circuits.
 
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You'll eventually find a use for the 16-Volt one also. I used to see them when I fixed some old computer screens.
It's usually better to buy a few more, as was suggested. Wrong continent, but the company I use starts lowering prices per unit even for like 3-5+ pieces of a $2 part.
I just wanted to include myself in the thread, I get excited when something gets fixed :D
Edit: audio caps are way overpriced.
Edit2: higher voltage caps often have slightly higher ESR (resistance) which has bearing on some circuits.
i already filed a return and they dinged $6 for shipping. but ill have a few spares of the correct ones. already got the usb socket on which was the "hard" part.
 
got it fixed, seems to be working. thanks for the help!

edit: they have confirmed it is working. i shoulda took a pic though, the cap looked pretty silly but it worked! thanks again!!
 
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