Caps from Nippon

[dirtyferret]

No not anime baseball caps but capacitors from Japan.

I'm tagging a few people as we have had this discussion in other threads but we have never had a thread for this discussion and I'd like to hear their opinions on the subject. That said all opinions are welcome and valid but lets use backed up facts when possible.
@Bill_Bright
@Shrek
@Bobaganoosh
@TimatPSUTest.com
@Veseleil

OK we all know what the marketing term means, a quality capacitor from Japan but it's really just a marketing term with no "official meaning" other than some sort of correlation to Nippon. Reviewers have even come out with their own "tier" list of quality caps (Aris posted his on Tom's) with Japanese companies like Panasonic, Rubycon, and Hitachi being at the top followed by Taiwanese caps in a secondary tier and the "too be avoided at all cost" chinese caps towards the bottom...but...a couple of years ago I heard from some brands/manufactures that they would swap out their Japanese caps for Teapo caps if they could but because of marketing they are painted into a corner with using Japanese caps. Since brands/oems don't release their in house testing we really don't know the quality of caps outside of the specs of the cap and its reputation...until recently. Aris started testing caps and while his test may not perfectly represent PSU cap performance and life span it's 1) pretty good, 2) something is better than nothing and 3) all we currently have in terms of testing until the brands/oem release their in house findings (don't hold your breathe).

The results show caps from Teapo heading up the performance test not the ususal suspects from Nippon (although they do perform well) and that said these particulair caps were actually made by Jamicon for teapo. Jamicon was a chinese company recently aquired by the taiwanese Teapo and had previously made caps for themselves as well as received outsourced orders from Japese company Rubycon. Jamicon was listed by Aris in his Tom's cap tier as tier 3, Teapo as tier 2 and Rubycon as tier 1.

So the discussion is, should we open up the "quality caps" list to other maufacturers who may not be from Japan?

This is not a discussion of "you should always buy PSU with caps from this country". There is nothing wrong with demanding all quality caps from Japan but rather should there be a discussion with demanding quality japs from taiwan or even china if they perform just as good or better that "100% Japanese Capacitors" while keeping the PSU price down?

 

[Shrek]

I understand that while the quality of electrolytic capacitors varies, I read that solid state capacitors don't vary so much, so the solution might be to simply use solid state capacitors.

 

[dirtyferret]

so the solution might be to simply use solid state capacitors

I'm not sure the price difference between aluminum vs polymer, maybe you know from ebay and other sites, but for most of these brands/oem it comes down to every nickel and dime saved

 

[ty_ger]

"Japanese Capacitors" is marketing for a track record of quality and reliability. Nothing more. If you can compete against that notion, you can start marketing something different. Then, you see what the market chooses.
I think it would make more sense to market temperature rating, life expectancy, tolerance range, esr, and esl instead, but whatever.

 

[Shrek]

I'm not sure the price difference between aluminum vs polymer, maybe you know from ebay and other sites, but for most of these brands/oem it comes down to every nickel and dime saved

Jon Gerow himself confirms they are probably too costly
(5) JonnyGURU | Facebook

 

[dirtyferret]

I think it would make more sense to market temperature rating

a few brands will market "105c" but none of the other cap specs and some don't even say if it's all the caps or just the bulk

Jon Gerow himself confirms they are probably too costly
(5) JonnyGURU | Facebook

found this from Aris

So why not use polymer caps exclusively and forget about electrolytic caps and their problems? The main reason is that the increased ESR values of electrolytic caps actually help avoid unwanted oscillations, which can cause instability. Although low ESR is critical in ripple filtering, minimizing ESR in PSUs isn’t a good idea either. This is why some re-cap jobs don’t go as expected. On top of that, polymer caps have a limited voltage rating. This doesn’t affect their use on the secondary side much, but in the APFC converter, an electrolytic capacitor has to be used.

 

[Onasi]

Feels like “100% Japanese Caps” is nowadays for PSUs what “Genuine Italian Leather” is to, I dunno, car seats. It’s by itself a meaningless marketing blurb that doesn’t really tell you how the platform overall performs. I don’t think many tech savvy people are basing their purchasing decisions solely on that. It’s more like this - if the PSU is overall high quality and performs well in testing, then you can be fairly sure that the caps used are absolutely fine, be they Japanese, Taiwanese, Chinese, Kongolese, whatever. But a PSU that has fundamental issues won’t be saved by having these magical caps, 100% Japanese or not. It’s just something that marketers noticed as working and latched onto over the years, customers have started “expecting” it (we may say otherwise, but most people are very susceptible to punchy marketing) and here we are now. But I get why marketing has used this - PSUs are an eldritch mystery to most buyers and there isn’t much of excitement to be used for advertising. So they used what they could.

 

[Bobaganoosh]

I haven't dug into this super thoroughly, but the primary reason for the marketing is that there were some really crappy caps from China that were failing pretty regularly for a while. This led to some supplies buying only from reputable companies that happened to be in Japan and ever since that trend, "100% Japanese Capacitors" became a specification. Since then, a lot of the cap companies in China have improved dramatically and I think Aris's comment in that video really hit the nail on the head "you have to look at the model, not just the manufacturer" (paraphrasing a little). It's a bit harder, but you also would want to consider temperature ratings, long-term stability, etc. and not just voltage handling. It takes a lot of testing, time, and effort to try and make a list that compares all of that with data and evidence.

My professional experience is kind of funny here because most of the analog circuits I've designed were for aerospace and for circuits and components where we avoided electrolytic capacitors wherever possible. This did sometimes mean stacking a lot of ceramic caps, but we basically did whatever we could to do that because even the best electrolytic caps will fail before most of the other components when doing ruggedized designs. My current job still includes some aerospace (and "space-grade") designs, but not all of them are and I still find myself instinctually avoiding electrolytics when possible. Now, just to be clear, that's not possible on a power supply. They really need the big bulk caps to perform properly.

As an example, compared to what Aris tested in the video (16V caps), the largest surface mount MLCC I can get is 100uF, which is a fraction of the size in the video (or the 2200uF caps in the picture above), and I would personally pick Kemet, Murata, AVX (Kyocera), TDK, Vishay, Taiyo Yuden, or even Yageo, but I've never heard of the Chinese brands listed in Aris's tier list. I'm also buying from certified US distribution like Mouser, Digi-Key, Newark, etc. and some of those brands aren't even available to me. I would also avoid Panasonic (which Aris lists as top tier) because they tend to change which models they make regularly, which leads me to obsolescence replacements and that's an avoidable headache (which has nothing to do with quality).

Because of my experience with MLCCs, if I was picking an electrolytic, I'd be biased towards Kemet, Vishay, EPCOS, or Wurth...which are not nearly as common in PC PSU's as Rubycon, Nippon, Panasonic, etc.

the TLDR here is that while I know what I would pick for myself, I'm not even dealing with the same distribution as let's say SeaSonic/Channel-Well/Super Flower/etc. and I don't have experience with the parts they're picking, so when I'm buying a PSU, I'm going to have to trust the reviewers a bit and hope that they're in contact with QA/RMA departments and hearing what caps people are having problems with to help guide my decision-making. I'm also at a point in my life where I'm spending pretty good money on a power supply from a company I'm pretty sure doesn't want to deal with regular RMA's from capacitor failures...so I'm really hoping they're going with quality.

All that said, I can anecdotally say that I've seen a general drop-off in quality of a huge variety of parts from all industries and all countries-of-origin. It seems like since Covid, supply chains had to push so hard to catch up with shortages that too many corners were cut, too much experienced staff was lost (people went home and didn't come back for one reason or another...lots of people changed careers at that point), and too much rushing was done...so I'm just personally a bit skeptical of everything. Or at least...my expectations have been lowered. Maybe things will improve or stabilize with time, but every market I look at seems to have completely unrealistic expectations of growth and profit and quality is getting shoved aside in the process. Maybe I'm just jaded, idk. Sorry for off-topic, but it's hard to have a baseline sometimes when you have a hard time relying on the "old standby's".

 

[dirtyferret]

Feels like “100% Japanese Caps” is nowadays for PSUs what “Genuine Italian Leather”

lol, I literally was going to use a "made in Italy" shoe example but thought it would be too off topic (still is just funny you kind of went there as well)

 

[Shrek]

a few brands will market "105c" but none of the other cap specs and some don't even say if it's all the caps or just the bulk


found this from Aris

So why not use polymer caps exclusively and forget about electrolytic caps and their problems? The main reason is that the increased ESR values of electrolytic caps actually help avoid unwanted oscillations, which can cause instability. Although low ESR is critical in ripple filtering, minimizing ESR in PSUs isn’t a good idea either. This is why some re-cap jobs don’t go as expected. On top of that, polymer caps have a limited voltage rating. This doesn’t affect their use on the secondary side much, but in the APFC converter, an electrolytic capacitor has to be used.

I would not use anything but 105°C except for the primary capacitor

Notes on the Troubleshooting and Repair of Small Switchmode Power Supplies (repairfaq.org)

• "Electrolytic capacitors exist in (at least) two different temperature ratings: 85 C and 105 C. The latter are obviously more temperature resistant. Unfortunately they also tend to have a higher ESR than their 85 C counterparts. So in an application where the heat is due to I^2 * ESR dissipation, the 105 C type may actually be a *worse* choice!"
• "ESR is usually something to be minimized in a capacitor. However, where the original design depended (probably by accident) on a certain ESR, this may not always be the case"

The results show caps from Teapo heading up the performance test

I have had no problems with Teapo, but it is not normally performance that concerns me but rather endurance.

My EVGA 500W1 uses Teapos, and I am happy with that.

 

[dirtyferret]

but it is not normally performance that concerns me but rather endurance.

would love to see some in house testing from corsair, seasonic, CWT, FSP, etc., on that but one thing to remember is Rubycon is not going to tap Jamicon if they feel they may face a massive recall. Among OEMs, Rubycom is up there a s one their quality vendors.

 

[Shrek]

Aris started testing caps

I am not at all sure about the utility of over-voltage testing and am not convinced that it is indicative of life under normal conditions.

 

[R-T-B]

I am not at all sure about the utility of over-voltage testing and am not convinced that it is indicative of life under normal conditions.

That's a valid point. It's probably the only accelerated wear metric we have sadly.

 

[Bill_Bright]

"Japanese Capacitors" is marketing for a track record of quality and reliability. Nothing more.

^^^This^^^

Just because a capacitor is made in Japan, that does not automatically make it superior. Claiming a device has Japanese caps is purely a marketing ploy.

Mexico, Taiwan, China and Timbuctoo are fully capable of making quality caps too.

When cheap electrolytic capacitors that bulged and leaked were a widespread problem years ago, just a couple Japanese companies were the only ones at the time that could immediately ramp up production to meet the supply demands for "solid" (NOT "solid state" - but "solid" as opposed to liquid) caps. Had those factories been located in South Korea, the marketing would have been all about "South Korean" caps, not Japanese.

I will also say the problems with leaking/bulging caps was almost 20 years ago. It is not the plague today it was then. Yes, leaking and bulging electrolytic caps still happen. But today, it is typically due to abuse (improper cooling or excessive - out of spec - voltages) and not due to inferior design, poor manufacturing techniques, or budget cutting resulting in cheap and/or the wrong cap for the job as it was many years ago.

Or the leaky, bulging cap was just the result of a manufacturing defect. Until Man can create perfection 100% of the time, there will always be samples that are not perfect.

Point being, there are, after all, such things as "quality" electrolytic capacitors that manufacturers can use too. It is just up to those makers to remember the lessons of the past, and not try to cut the budget with inferior, or wrong-for-the-job caps.

 

[natr0n]

get samples and a tester unit and not worry

 

[Ruru]

I prefer that my PSUs have 100% Japanese caps, but Taiwanese caps on some parts (like on the modular connectors boards) are practically fine.

But caps from PRC China are mostly meh.

 

[stahlhart]

Nichicon from Digi-Key has never failed me. Really liked Panasonic FC/FM also, could get everything I needed 10-15 years ago but sadly they are now gradually being obsoleted value by value.

 

[Shrek]

While I am generally happy with 85°C capacitors on the primary, I decided to move those on my EVGA 500W1 power supplies from a tier 2

• 85°C 400V 270μF (Elite)

to a tier 1

• 105°C 420V 470μF (Nippon Chemi-Con)

since there was space on the board.

Disclaimer: do not mess with power supplies as the main capacitors can carry a lethal charge even when the supply is not plugged in.
Teen electrocuted while taking apart unplugged computer (today.com)