Ceramic instead of Electrolytic

[amanoob]

A cap on a old Mobo was shot and I didn't feel like ordering a part of the internet. I asked a friend to get a capacitor 680 UF
10V
LE 105C°
GSC
I didn't say Electrolytic but I assumed the one he would get would be.


And he got me a ceramic 680Uf 2% SAN300v. Would I be able to use this, I think not but I want to make sure. Thank you.

[Th3_uN1Qu3]

Re: Ceramic instead of Electrolytic

I don't think they make ceramic caps in values that high... are you sure you read the value right? Maybe it's 680nF, and in that case you definitely won't be able to use it.

[ratdude747]

Re: Ceramic instead of Electrolytic

I don't think they make ceramic caps in values that high... are you sure you read the value right? Maybe it's 680nF, and in that case you definitely won't be able to use it.

agreed. not to mention ceramic caps behave differently... there could be ESR issues.

[amanoob]

Re: Ceramic instead of Electrolytic

Thanks, I figured it wouldn't work. BTW the cap says 680 and then it has a equal sign with a line through it.

Do you think this would be a suitable replacement? http://search.digikey.com/us/en/prod...1745-ND/589486

[b700029]

Re: Ceramic instead of Electrolytic

I'd like to see pictures of this 680uF 300V ceramic cap.

[Th3_uN1Qu3]

Re: Ceramic instead of Electrolytic

If it says just 680 then it's a 68 picofarad not uF... A few orders of magnitude off. FYI: http://www.electronics2000.co.uk/cal...calculator.php

That cap you found on digikey is general purpose and not for use on motherboards or switching power supplies, it has too high ESR and too low ripple current. This will work in that position: http://search.digikey.com/us/en/prod...1644-ND/756160

[PeteS in CA]

Re: Ceramic instead of Electrolytic

A 680uF, 300V monolythic ceramic cap would be huge! And the temperature coefficient would be horrible (e.g. the cap might be 50% of its nominal value inside a warm case ... maybe lower). I'm also highly prejudiced against large form-factor monolythic ceramic caps because they are brittle and tend to be destructive to PCBs when they crack and short.

[amanoob]

Re: Ceramic instead of Electrolytic

I found out it is a mica cap. I had no idea what they were before I searched for it.


The only thing I am worried about with the cap from the link is that the one I have is 15mm x 8mm.



Thanks again for all of the help. I plan on giving the computer to my little brother.

[Th3_uN1Qu3]

Re: Ceramic instead of Electrolytic

A look at the board will tell you whether a 10mm diameter is going to fit or not. My guess is it will.

[PeteS in CA]

Re: Ceramic instead of Electrolytic

Yep, mica dielectric, 680pF.

[Agent24]

Re: Ceramic instead of Electrolytic

If it says just 680 then it's a 68 picofarad not uF... A few orders of magnitude off. FYI: http://www.electronics2000.co.uk/cal...calculator.php

I have noticed that when capacitors are labelled directly in pF they are done so without the multiplier. Hence 68 would = 68pF

Therefore, I would suspect that being labelled 680 would actually = 680pF.

Of course, the only way to know for sure is to check with a capacitance meter or if you have the datasheet.

[PCBONEZ]

Re: Ceramic instead of Electrolytic

If it says just 680 then it's a 68 picofarad not uF... A few orders of magnitude off.

Right

That cap you found on digikey is general purpose and not for use on motherboards or switching power supplies, it has too high ESR and too low ripple current.

Wrong.

PW is a Low ESR cap exactly equivalent to Panasonic FC.
That grade is commonly used on motherboards and in SMPS for the small caps.
On much older boards [P-2] they are even used in Vcore.
In fact I have 3 old Intel P-2 slot 1 boards in stock and they all have PW and FC in Vcore. [Big fat ones.]
[2 have one series and 1 the other.]
.
In SMPS PW [and PW grade] are REALLY common except for the final OP filter caps.
.
.
That said....
GSC LE is a higher grade than PW/FC for ESR.
The PW won't work but it's not because it isn't a low ESR cap.
It's just not low -enough- to replace this specific GSC cap.
.

[PCBONEZ]

Re: Ceramic instead of Electrolytic

GSC LE 680uF 10v
... 8x14mm 950-Ripple .060-ESR
... 10x12mm 1030-Ripple .053-ESR

It looks like the 8mm so:

Equivalents
http://search.digikey.com/us/en/prod...376-ND/2433510
FR 8x11.5mm 950-Ripple .056-ESR [extra short...]
http://search.digikey.com/us/en/prod...1645-ND/756161
KZE 8x15mm 995-Ripple .056-ESR

Upgrade
http://search.digikey.com/us/en/prod...2365-ND/613726
FM 8x15mm 1240-Rippl .041-ESR
.