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Electronics => Repair => Topic started by: multifrag on October 23, 2015, 09:38:55 am

Title: In search of SMD Electrolytic Capacitor
Post by: multifrag on October 23, 2015, 09:38:55 am
I'm trying to find:
E32M
220
16v

SMD Electrolytic Capacitor. Diameter is 10mm and height is about 7mm. Trying to fix coil whine in a gpu and as it is an old gpu I'm guessing its the dried out cap making the coil whine.

(http://i.imgur.com/lnyqtUv.jpg?2)
Title: Re: In search of SMD Electrolytic Capacitor
Post by: singapol on October 23, 2015, 01:17:15 pm
It does not have to be identical or exact. Just the normal type 85 degree or if you want long life 105 degree
but how do you know this cap is the problem. Try to measure esr in circuit if you have esr meter. But if you have the money just repace it. It would be helpful if you know where it is located on the pcb like power supply or fan. Coil whine in gpu...you mean inductor, fan normally do make some kind of noise maybe fan motor is worn out. Most important is the footprint of new cap fits the solder pads.
Title: Re: In search of SMD Electrolytic Capacitor
Post by: free_electron on October 23, 2015, 01:31:57 pm
the blue ink means this is an oscon.
Title: Re: In search of SMD Electrolytic Capacitor
Post by: singapol on October 23, 2015, 01:38:27 pm
the blue ink means this is an oscon.

Should it not be purple? Oscon is good if you can get it.

http://www.digikey.com/en/product-highlight/p/panasonic/os-con-capacitors (http://www.digikey.com/en/product-highlight/p/panasonic/os-con-capacitors)
Title: Re: In search of SMD Electrolytic Capacitor
Post by: mariush on October 23, 2015, 05:14:22 pm
It's not OSCON, from what I can tell from the picture (tiny logo on top) it's a Nippon Chemi Con polymer capacitor.

Replace with any low esr polymer capacitor. If you can't find 220uF in the size you need, you'll be safe with 180uF, just like you'd also be safe with 270uF.

And in a pinch, you can go with leaded polymer capacitors and just bend the leads to be on top of the smd pads when you solder them... it will look ugly but it will work.

See http://uk.farnell.com/aluminium-polymer-capacitors (http://uk.farnell.com/aluminium-polymer-capacitors)  or their "uk retail" site: http://cpc.farnell.com/components-passive_capacitors (http://cpc.farnell.com/components-passive_capacitors)

You may also be able to replace it with an electrolytic capacitor but it would have to be something with low esr. 470uF 25v rated capacitor may be just low enough to work but I'm not sure if the extra capacitance would be a problem or not.
Title: Re: In search of SMD Electrolytic Capacitor
Post by: multifrag on October 23, 2015, 05:27:57 pm
It does not have to be identical or exact. Just the normal type 85 degree or if you want long life 105 degree
but how do you know this cap is the problem. Try to measure esr in circuit if you have esr meter. But if you have the money just repace it. It would be helpful if you know where it is located on the pcb like power supply or fan. Coil whine in gpu...you mean inductor, fan normally do make some kind of noise maybe fan motor is worn out. Most important is the footprint of new cap fits the solder pads.

Its either the R23 Coil which is sealed and should not do that or more likely the capacitor near by which has dried out. Similar thing was happening with power supply and by replacing the caps I've eliminated the problem. Most of the times if the coil is open type I would just put some epoxy and it would minimize the vibrations, but there is little I can do with the closed ones apart replacing them.
PCB image for reference:
(http://images.bit-tech.net/content_images/2013/04/amd-radeon-hd-7990-6gb-review/7990-8b.jpg)
Title: Re: In search of SMD Electrolytic Capacitor
Post by: multifrag on October 23, 2015, 05:30:06 pm
It's not OSCON, from what I can tell from the picture (tiny logo on top) it's a Nippon Chemi Con polymer capacitor.

Replace with any low esr polymer capacitor. If you can't find 220uF in the size you need, you'll be safe with 180uF, just like you'd also be safe with 270uF.

And in a pinch, you can go with leaded polymer capacitors and just bend the leads to be on top of the smd pads when you solder them... it will look ugly but it will work.

See http://uk.farnell.com/aluminium-polymer-capacitors (http://uk.farnell.com/aluminium-polymer-capacitors)  or their "uk retail" site: http://cpc.farnell.com/components-passive_capacitors (http://cpc.farnell.com/components-passive_capacitors)

You may also be able to replace it with an electrolytic capacitor but it would have to be something with low esr. 470uF 25v rated capacitor may be just low enough to work but I'm not sure if the extra capacitance would be a problem or not.

Would something like that work as a good replacement as the size fits just is a noname:
http://uk.rs-online.com/web/p/aluminium-capacitors/0268269/ (http://uk.rs-online.com/web/p/aluminium-capacitors/0268269/)
Title: Re: In search of SMD Electrolytic Capacitor
Post by: mariush on October 23, 2015, 05:44:24 pm
The one you linked to is not a noname, it's actually made by Nichicon which is one of the best capacitor manufacturers. Yes, that series would be suitable.