On Sat, 21 Nov 2009 04:22:04 -0800, William Sommerwerck rearranged some electrons to say:
It not just that... go search for "tin whiskers". We have nothing to fear from the machines taking over, they will all fail a long time before humans do.
On Sat, 21 Nov 2009 15:26:08 +0800, Man-wai Chang to The Door (28800bps) rearranged some electrons to say:
You cannot get large capacitance values in a small package size with a ceramic dielectric.
So why do the good brands tolerate those conditions so well while the same old junk brands don't? And contrary to what you say, most of the caps aren't in hot spots but are running at under 60 Celcius
doesn't
But the problems with junk capacitors showed up way before the switch to lead-free solder, and only one of my RoHS mobos has so far popped a cap, probably more because it's newer (late 2007), not because it's better, but it has the same OST brand junk caps.
The real fault lies with the makers of junk, period.
Ok, I stand corrected.
Groan. So much for my method of using the case style to recognize the difference between electrolytic types.
So that's the trick to recognizing the difference. Thanks.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
So, what exactly are you saying ... ? That better quality components tolerate abuse more readily than cheapo crap ones ? Very profound ... I don't think that is actually at odds with anything I said, is it ? I seem to recall in my original reply to William that part of the reason that he may have had good luck in regard to electrolytic failure, is the fact that he has tended in the past to buy better quality equipment where the manufacturers have been prepared to "design to a better spec with a few cents more spent on components ..."
As far as your contention that most of the caps that fail are running at under 60 deg and are not in hotspots, that may be true if you are talking just mobos, which are a bit of a special case in that apart from all the problems that have been caused in the past with boards built using caps with fake electrolyte, the caps that fail are all decouplers on constant DC rails, and are rated voltage wise pretty close to the continuous voltages that are applied to them. Even accepting that, many of the decoupling caps that do fail on mobos, are sited very close (by nature of the job that they have to do) to LSIs which *do* run very hot.
The caps that I am talking more about in general, are on switch mode power supplies, where they are subjected to huge stresses from the high frequency pulse currents that they have to endure, and the self heating caused by this in all but the most expensive types, very specifically specced for use in these positions. Further, the ones that fail most regularly are, without doubt, the ones positioned close to heatsinks. I replace hundreds every year in the course of my daily work. Although the caps positioned on switchers are by far the most common ones to fail, they are by no means the only ones. I also replace many in other circuits, for instance audio output stages, where failed ones are almost invariably close to heatsinks.
I don't dispute that junk capacitors have been failing for a long time, but that is for the very good reason that they are ... well ... junk, not to put too fine a point on it. However, if we take junk out of the equation, anyone directly involved at the sharp end of electronic service will tell you, as I do now, that over the last five years or so, the incidence of electrolytic failure has increased a lot with the increased use of switchmode power supplies in all sorts of consumer equipment, and the unstoppable rise of Chinese designed and manufactured equipment, where many good design practices, such as ensuring adequate ventilation, are not observed on cost grounds. As to whether the increased process temperatures of lead free soldering has had any effect on long term reliability of electros, I really don't know for sure. I could be wrong, but it seems to me that over the last couple of years, the incidence of electrolytic failure has increased even more than the trend of the last 5 or 7 years, so it was just a thought in that this was something else that had changed in that timeframe, and may have been a contributory factor
Some of the fault lies with the makers of junk, agreed. But not all, by any means.
Arfa
I'm in complete agreement with Arfa. Internal heating caused by the ever increasing switch mode power supply frequencies is the most common cause of failure. High external temperatures don't help one bit since it reduces the components ability to get rid of internally generated heat.
A place where I'm finding more and more capacitor failures is in the memory supply voltage regulator circuits, sometimes causing CPU failure in addition to memory damage.
--
Best Regards:
Baron.
Generally true. This is old (2005) but the best I could find:
6 pages. The hottest they found was 70C and that was in an odd corner of the MB for no obvious reason.More of the same:
However, these show some chips getting up to 99C. Ouch.
Worse. The caps are not on constant DC. There are huge ripple currents going through these caps at they heroically try to filter the DC voltage. You wouldn't need low-ESR caps were it not for the heating caused by the internal resistance and this ripple current. It's even worse in power supplies.
Yeah, but along with the general decrease in quality, there has been proportional decrease in price. It's price that driving the decline in quality. Running the operating temperature and voltages near the point of failure is one way to save on costs.
Good point. I have no idea if there is a correlation but it seems worthy of investigation.
They wouldn't make junk if consumers didn't demand low prices. There are usually "premium" versions of almost any consumer product, but few can afford the price. (If you want quality, be prepared to pay for it). Personally, I prefer to blame the government for literally everything, but maybe not this time.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
he may
That better quality components tolerate abuse more readily than cheapo crap ones ? Very profound....
I'm just saying that low quality is probably a worse problem than the heat (power boards for LCDs are sparse) or high currents. The usual suspects have the same specs as the good components do, at least when new, and their lifespan specs are also identical.
How much would the retail cost of a computer power supply or motherboard etc. increase if they were made to last twice as long? Five times as long? Ten times as long?
-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!
How much bigger (in volume) are polymer capacitors than electrolytics for the same value?
Are there any types of capacitors with substantially better life than electrolytics that are small enough to replace electrolytics? If so, how do they compare in price?
-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!
Both Asus and Gigabyte make motherboards that they claim use all solid polymer capacitors. I doubt that they would lie about something like that.
-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!
The usual markup from cost to sales to retail prices is about 4.5 times. It's somewhat lower for commodity electronics, perhaps 3.5 times. It's somewhat higher for newly introduced products, where the R&D costs need to be recovered quickly. I'll call it about 4 times so I can do the math without a calculator. That means that for every $1 increase in parts cost, Joe Consumer gets to pay out $4 at the cash register.
The problems start when there are competing products. I call it the Walmart effect. Walmart, Kmart, and many online vendors specialize in selling solely on the basis of price. If there are two competing products, differing only a few pennies in selling price, *ALL* their orders will go to the lower priced product, with nothing to the higher priced equivalent. Walmart aggravates the effect by setting the price at some artificial low level, and challenging their vendors to meet their price goal. If they fail, then they either take a loss selling to Walmart, or all the business goes to the competition.
Much as I don't like it, such cut throat pricing practices are becoming the norm in computer sales. If I were to design and produce a premium and long life computer product, I can forget about the mass market, volume dealers, and most direct sales channels. I would have to rely on distribution and probably heavy advertising, which dramatically raise my costs. Do you think a $50 Monster Cable power strip is really any better than a $5 hardware store equivalent? It is a little better built, but the rest of the price tag is distribution and advertising.
Incidentally, if you want to see premium electronics, the audiophile market is a good place. Need a $1,000 premium power cord?
That's what it takes to sell a premium product.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
I don't know the specific numbers for those multipliers.
However, I've seen some motherboards for sale recently which proudly stated that they use all solid-polymer caps in their CPU power supply circuit. They come at some price-premium but it didn't appear to be outrageous.
--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
It seems to me that there is a good opportunity here for other retailers. If a retailer sold only electronic goods that were well made and well designed, they could sell them for ten to thirty percent more than the junk sold at Walmart and Kmart.
I think many consumers would be willing to pay a little extra for devices that would probably last four to ten times as long. This would be especially true if they had two (or more) cheap-junk brand devices fail.
The retailer could require vendors to only use non-junk capacitors with voltage ratings at least three times the voltage the capacitors would be exposed to. They could also require that no part of the device ever get more than 30 degrees warmer than the temperature of the room it is used in.
The devices could have much longer warranties and the store could advertise itself as "The quality store". I do not think this would require excessive advertising, especially after the first few years.
-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!
There are such businesses. However, they are small and the number is shrinking. I've lived in the same area for about 35 years and have observed that number of such retailers decreasing. Few have grown in size over the years, which is a good indication of their viability. I discussed the quality and service issues with the former owner of one of these businesses. He noted that competition from the "big box" stores was a problem, but that there were usually those that were willing to buy from a locally owned business for a variety of reasons. However, with the introduction of online shopping, the situation changed. Online vendors offer the same premium products, but without the overhead inherent in maintaining a retail store. Some online vendors don't even have an inventory and simply drop ship from the factory or a fulfillment house. The result is that consumers that know exactly what they want, will tend to buy online. Much as I like the idea of supporting a local business, it's difficult to justify when there's as much as a 30% difference in price.
I don't know anything about Walmart, but Kmart experimented with stocking premium products next to the usual cheap junk about 10 years ago. The idea was to give shoppers an expanded choice. At the time, I took one look and predicted disaster. For all I know, it may have been intentional. What Kmart did was mix the junk and the quality together on the same isles. You could tell the difference by the name and price, but otherwise they were indistinguishable. Unfortunately, Joe Sixpack couldn't tell the difference despite national advertising indicating that Kmart was now selling "name brand merchandise". The idea bombed. It might have worked if Kmart had implemented some form of "product differentiation" where the distinction between cheap junk and name brand was more apparent. There were also other factors, such as consumers tend to buy at retail stores that match their buying habits. Most shoppers would not intentionally shop at a "nothing but the cheapest" store, if they were looking for quality or brand name.
I'm sure there are those out there. Whether they can support a retail business is debatable. I spend far too much time at the local electronics recycler:
I literally cry (for real) when I see the stuff that gets tossed. Most of it can easily be fixed. Much of it is still working, but only needs a cleaning. Grey Bears has a minimal retail store to sell some of the refurbished equipment, but it barely breaks even. The only buyers are other dealers and hackers both of whom know exactly what they're buying and what it's worth. Joe Sixpack and bargain hunters are usually lost.
If you want to see how someone lives, just look at their trash. You'll learn more about their buying habits from the trash than from anything you see in their house or business. It's the same with eWaste. It's not unusual to see a complete multifunction inkjet printer/scanner/copier/fax, in the box with the disks and docs, tossed because it "died". Closer inspection finds that someone forgot to remove the plastic tape from the inkjet cartridge.
The buying habits of Joe Sixpack are evident (to me). He assumes that electronics will have a short lifetime and treats it accordingly. As soon as something gets a bit old, he'll be in line at the local Walmart or Cosco for a replacement. He has no technical abilities and is unable to distinguish between quality and crap. I've seen this first hand as some of my more astute friends enlist my help to decide which HD TV is appropriate. It takes me at least an hour or two of reading reviews and looking at the FCC ID site, to make a determination. Joe Sixpack might spend a few minutes with a sales droid.
Bottom line: You're giving far too much credit to the average consumers abilities to benefit from long life products.
Welcome to Realityland. A former ladyfriend was a buyer for a large department store. The problem is that models change faster than the order cycle. Coupled with just-in-time delivery, what was ordered by the buyer is often quite different from what was ordered. The stores actually benefit from this practice as they always want the "latest model" and not it's predecessor, which was on the original order. If you compare the original orders, with the stocking inventory, my guess is that perhaps 30% is the same. If they reject the delivery, then they have nothing to sell. The usual compromise is that the manufacturer is required to accept all returns, no matter the reason. That's suppose to give them an incentive not to ship junk.
More reality. The name of the game in big retail is turnover. My guess(tm) is that the TV section at Costco is expected to turnover
*ALL* their inventory in perhaps 60 days. Warehouse and floor space are expensive. If products just sit there, there's no revenue and the space becomes even more expensive. This is one reason why stores have "clearance" sales. They want the space to be used for products that move, not for storage.You can't run a quality based retail business, selling long life established products, in large quantities, that way. Reliability takes some time to produce. You can just toss in more expensive caps and expect the overall reliability to instantly improve. There may be other parts that are running at the bitter edge of premature failure. By the time the bugs get shaken out of a production product, the next two or three replacement models will be in the production pipeline. The result is that old problems with older products never really get fixed. They get fixed in the design of the replacements. As a result, most products are permanently stuck at Rev 1.0. If you're going to sell quality, the inventory turnover will need to be stretched.
The good part about all this is that problem products just don't last very long. Soon after the problems are found, the replacements appear in the stores. The replacements have all the latest features, use all the latest designs, and follow all the latest fashion trends. Since inventory is minimal, the prices tend to be low. This is what consumers really want; features and price. Quality is assumed or tolerated.
Back to the original topic... I think there will be widespread use of solid polymer caps in place of small electrolytics despite the price. However, it's not because of some mythical search for an improvement in quality. It's because the crappy counterfeit electrolyte is still in the system now 10 years after it was first introduced and shows no indication of going away. Respected manufacturers are starting to see their reputation go down the drain over these parts and are probably looking for a fix, which solid polymer caps offer. If they advertise the new and improved replacement, they can also justify the increased retail cost.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Maybe ten times as much, if you are selling real quality.
Have you ever designed consumer electronics, or worked in electronics manufacturing? have you ever tried to buy top quality components, or run 100% incoming inspection. It isn't cheap.
You don't understand much about electrolytics, do you? The ESR goes up with the voltage rating, along with the physical size. That requires a different board layout, which raises the resistance & inductance of the copper traces, which causes more problems. It becomes harder to filter the ripple current from the CPU power supply, causing more erratic behavior.
It is the ripple current through the electrolytic that degrades it, to the point of failure. All of this is the reason that the electrolytics for the CPU are so close to the CPU socket. Your method would cost more, and have a shorter life.
That's a joke? Even mainframe computers with dedicated air conditioning ran hotter than that.
You can call yourself whatever you want, but you are not going to get much quality improvement for a 30% (retail) cost increase.
-- The movie \'Deliverance\' isn\'t a documentary!
... and are cursed with brand new problems.
I do service work for several retailers of 'quality' consumer electronics, and all are having a hard time of it. Their only customers now are those who can genuinely afford the stuff. The others who aspired to being owners, and saved their hard-earned for however long in order to enable them to become owners, are long gone, with whatever spare money they have, going to keeping a roof over their heads, and putting food on the table. Times is 'ard, my friend ...
As I repair the stuff for a living, you would think that I would know better, but even I buy what I know to ultimately be junk. Just a few weeks ago, I bought a DVD player to replace the 'good' Tosh that I had owned for some time. It came from the local food supermarket, and was some kind of unknown junk name. But you know what ? It plays any disc region that you put in it, any home burn disc type and format both CD and DVD, came with a complete set of connecting cables, and even a full function credit card remote handset. And what did it cost ? Fifteen quid, that's what. And it has a year's full warranty. Even if it failed within the warranty period, it's just a throw away item. Go buy another. Half a dozen pints of beer ...
Arfa
If you find yourself cursed, hire an exorcist.
Yep, we're all doomed. I'm looking at Rev 1.0 of a just released consumer electronics product. All of the ASIC's inside are custom. Most of the glue chips didn't exist 6 months ago. The date code on some of the parts are about 2 months ago. The plastic doesn't quite fit. The firmware is a bugfest with the latest update scheduled to hit their web pile real-soon-now. The user interface resembles a student effort which will fail any usability test. No, I won't disclose the product. My point is that if you want the absolute latest, you're going to have to tolerate a certain level of rush to market, complete with bugs.
Most products are NOT revolutionary. They evolve based on previous products or are stolen from the competition. The problem is that as one product is manufactured, there anywhere from one to three future replacement versions of the same product somewhere in the design cycle. With such a derangement, even if the problems were known on the original product, the fixes will not appear in the updates or replacements until after one to three hardware revisions.
However, there's hope. With hardware bugs, it's not unusual to use software and firmware updates to work around the bugs. Where this goes awry is when vendors decide that it's not worth supporting products that they no longer sell, making old bugs permanent. I give great credit to some manufacturers (such as Linksys) for producing firmware updates for products or versions that haven't been sold for many years.
The point is that bugs and glitches are inevitable with rush to market, but can be dealt with given sufficient time. It's the sufficient time that's really the problem. Many suppliers of retail products are sufficiently isolated from the retail sale that they have no real interest in supporting end users, much less even identifying themselves. By the time a complaint dribbles back down the supply chain, it's usually lost. If it does arrive, it usually lands on the very bottom of the priority pile, or is so late that the next release or model of the product is in production making it too late to do anything about the old product.
Even if the factory has a long term delivery and release contract, there's still a problem. Features and functions get added faster than bugs get fixed. The result is a feature infested but seriously buggy product that never seems to get fixed. Most manufacturers recognize this and compensate by slowing down the development cycle enough to do minimal testing, debugging, and damage control.
Unfortunately, not much can be done if defective or counterfeit parts are used. Incidentally, counterfeit components and products are a serious problem and involve far more than just low-ESR capacitors. I had a series of motherboards fail due to bulging capacitors. There were about 15 machines involved. Only 5 of them had bad caps. I removed some caps from both the good and bad boards and tried determine if there was a measurable difference. Yep. The ESR was radically different. Yet, the package, labeling, color, coining, and everything about the caps were identical. I could not tell the difference visually. What this tells me is that there are still some bad caps mixed in with good caps in the manufacturers inventory. It may only be one bad reel of caps among hundreds, but it only takes a few caps to trash a product. It's also possible that the capacitor manufacturers are shipping old inventory in order to make a fast dollar. Hard to tell from here.
What I find amusing is asking friends and customers how long they expect some consumer electronics device to last (with some repair). The older ones expect their TV to last as long as their hand wired
1960's Zenith TV. 20 to 30 years would be typical. Younger buyers, that have had some experience with contemporary product lifetimes will usually say 5 to 10 years at best, as if this was considered normal.Quality, features, price. Pick any two.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
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