Good brand caps?

[BigBrother]

I need to replace a capacitor in my car's on-board computer and I need at least one (farad number pending). I don't know exactly how hot it gets down there but this is texas, so I assume it gets blazing hot. any recommendations for an extra heat-tolerant cap?

[Rerouter]

vishay or panasonic are my preferences,

aim for the most hours at the highest temperature your willing to pay for, (each 10 degrees hotter roughly corresponds to half the hours)

edit: panasonic not phillips :/

[T4P]

Rubycon has some 130C caps seen in the phillips LED bulbs,
followed by
Nichicon
Epcos
Panasonic
Nippon Chemicon
United Chemicon < - I assume they are the same?
Sanyo
LOW ESR Electros?

But which type are you looking for?
Ceramic? MLCC? < AVX, Kemet many others
Polyprop? Poly cap? < Flim caps WIMA, Panasonic
Mica? Tantys?

(why the hell is farnell selling Samwha caps ... WTF)

[mariush]

Farnell (Newark.com in US) is selling Rubycon RX series which is rated for 130c

Technically, their specs kind of match the specs of other series of theirs, but at different voltage ratings.  I mean if you have a 470uF 10v capacitor you want replaced, you can match the specs with a 470uF 25v Rubycon RX and get close enough with a 16v rated one.

I only use Nichicon, Rubycon, Panasonic and occasionally United/Nippon Chemi Con ... and if it's really a hard to find capacitor, I wouldn't turn down a Samxon.

[FenderBender]

vishay or phillips are my preferences,

aim for the most hours at the highest temperature your willing to pay for, (each 10 degrees hotter roughly corresponds to half the hours)

Hmm I don't remember really ever seeing any Vishay caps that every popped out as being particularly great but I've only used them one or twice.

Here are my preferences:

Nichicon
United/Nippon Chemi-con (Yes these are the same company T4P).
Rubycon
Panasonic/Matsuhita
Sanyo

I remember Mouser carrying automotive grade Nichicons. I believe they were 150C.

Found them: http://www.mouser.com/_/N-scv7?Keyword=Nichicon+BX&FS=True

They don't stock too many values but perhaps they have a match.

Obviously only go up with voltage rating. Check what the current cap is rated for. So if it's 16v, get a 16v or 25v as others have said. Jut make sure it will physically fit.

[BigBrother]

here's a not-too-clear photo of the effed bits:
 

that big cap blew its load and presumably died 'closed' and fried the resistors.

edit: the caps are Nichicon 35v 220uF. can't really see what's on the other side. I'll be looking around for a schematic of this transmission control board.

[FenderBender]

Where is that board located? It doesn't look particularly rugged or made for high heat/abuse.

[BigBrother]

Where is that board located? It doesn't look particularly rugged or made for high heat/abuse.

1991 Honda Accord (LX?), Passenger Side towards the front of the foot area.

[FenderBender]

Ahh so this isn't in the engine bay. Well to be honest, you could probably just use a 105*C cap. That won't be getting too hot I don't think.

[T4P]

105C caps at 5000 hours would be plenty ...

[BigBrother]

FenderBender and T4p say 105C caps would do so I'll be getting caps locally. Am I SOL with the resistors without the parts list/schematic? those things are fried and without coating.

[SeanB]

Measure the value, and if they are open measure the value to half way and double it. Most likely a value from 3R3 to 10R if they are on the power inlet.

[BigBrother]

I'm finally getting around to looking for caps. These values... they're... insane. Is 865mA really an acceptable ripple value?

[T4P]

Actually very good for a 220uF cap 

common panasonics frequently come up to me at 420mA ... go figure 

[BigBrother]

Actually very good for a 220uF cap 

common panasonics frequently come up to me at 420mA ... go figure 

my brain isn't working. isn't higher ripple... bad?

edit: these are the ones I ordered:
http://www.digikey.com/product-detail/en/EEU-EB1H221/P13131-ND/813865
http://www.digikey.com/product-detail/en/UPJ1C331MPD6TD/493-5023-1-ND/3129360
I got two different ones because some posts on various forums note different caps squirting. the non-220uF being the most common whereas the one that blew on mine was... not noted.

[gxti]

The ripple current rating of a capacitor is the highest AC current you can put through it without causing damage. More is better.

[BigBrother]

The ripple current rating of a capacitor is the highest AC current you can put through it without causing damage. More is better.

but it's going in a car... I think it's all DC anyways.

[gxti]

That's a very misguided conclusion, to put it lightly. Unless you know how the capacitor is being used or at least have a schematic, you can't make any blanket statements like "it's all DC". It could be part of a switching power supply where it is subjected to high levels of alternating current.

[Monkeh]

The ripple current rating of a capacitor is the highest AC current you can put through it without causing damage. More is better.

but it's going in a car... I think it's all DC anyways.

Because cars are all a nice, stable, clean 12VDC. Totally not ~14VDC with massive amounts of AC ripple and severe under and overvoltage surges.

[FenderBender]

Lower ESR usually = higher ripple current rating. Just in case you were wondering.

[Flunze]

I need to replace a capacitor in my car's on-board computer and I need at least one (farad number pending). I don't know exactly how hot it gets down there but this is texas, so I assume it gets blazing hot. any recommendations for an extra heat-tolerant cap?

1F? Whatever.

You should put at least 2 in parallel, if you CAN do this, cause this will help against ripple currents. I am making a PSU soon and have only 85°C rated Caps. They where cheap. (2 Outputs) But I will put 2x10x2,2mF Caps in parallel, this definitely will elliminate any Ripple current from being to high, cause it splits over all the caps. This is not just much saver, it also costs a lot more. It only needs a few holes more on the PCB, but that is not a problem.


Do it like me, to save money.

[BigBrother]

I need to replace a capacitor in my car's on-board computer and I need at least one (farad number pending). I don't know exactly how hot it gets down there but this is texas, so I assume it gets blazing hot. any recommendations for an extra heat-tolerant cap?

1F? Whatever.

You should put at least 2 in parallel, if you CAN do this, cause this will help against ripple currents. I am making a PSU soon and have only 85°C rated Caps. They where cheap. (2 Outputs) But I will put 2x10x2,2mF Caps in parallel, this definitely will elliminate any Ripple current from being to high, cause it splits over all the caps. This is not just much saver, it also costs a lot more. It only needs a few holes more on the PCB, but that is not a problem.


Do it like me, to save money.

you want me to put 2 caps in an already restricted space? I spent an hour making sure the caps I bought were small enough with the right lead width.

[Flunze]

You don't have to.

It is just working much better, but if it does not fit inside, you cannot, of course. But if you want design something with high riplles, use more Caps in parallel, this will be much better.

[BigBrother]

You don't have to.

It is just working much better, but if it does not fit inside, you cannot, of course. But if you want design something with high riplles, use more Caps in parallel, this will be much better.

When you say in parallel... do you mean that it goes in one side of a cap, out the other side, into another cap like the first and repeat? I remember something like this being mentioned somewhere and saying that it was good up to like 3 or 4 caps and over that, it was just dangerous because of an effect it brought up.

[BigBrother]

The ripple current rating of a capacitor is the highest AC current you can put through it without causing damage. More is better.

but it's going in a car... I think it's all DC anyways.

Because cars are all a nice, stable, clean 12VDC. Totally not ~14VDC with massive amounts of AC ripple and severe under and overvoltage surges.

so... I should've bought caps with a larger ripple rating? something like 1.4A?