counterfeit component - Page 1
Forum section: electronics / general

author: Icarus
author_rank: Regular Contributor
timestamp: June 24, 2013, 07:30:34 pm
content: How can I avoid counterfeit components ? they make me insane !!!

author: Bored@Work
author_rank: Super Contributor
timestamp: June 24, 2013, 07:44:42 pm
content: Buy directly from the manufacturer if you can. If that isn't possible buy from an authorized distributor. If that isn't possible buy from a reputable distributor.

author: Unknown
author_rank: Unknown
timestamp: June 24, 2013, 07:47:44 pm
content: How big a problem is this? I buy components on ebay sometimes and so far I've had really good luck, even though they're pretty inexpensive. Is this something encountered frequently?

author: branadic
author_rank: Super Contributor
timestamp: June 24, 2013, 07:57:00 pm
content: My tip, avoid buying parts from asian ebay sellers.Particularly obsolete parts in hermetical packages like voltage references are one of the most counterfeit products and many hobbyists are not able to identify them as such.

author: Icarus
author_rank: Regular Contributor
timestamp: June 24, 2013, 08:10:32 pm
content: Quote from: branadic on June 24, 2013, 07:57:00 pmI've got almost 20 FAKE-LM317 and 30 FAKE-LM2576.I wish there is a quick test or something

author: mariush
author_rank: Super Contributor
timestamp: June 24, 2013, 08:12:57 pm
content: How did you determine they're fake?Especially LM317 which is made by dozens of manufacturers... seems kind of silly to fake.

author: c4757p
author_rank: Super Contributor
timestamp: June 24, 2013, 08:15:12 pm
content: Yes, China definitely churns out (probably marginal) working no-name LM317s by the metric shitload. Not sure about LM2576 though.

author: Monkeh
author_rank: Super Contributor
timestamp: June 24, 2013, 08:20:29 pm
content: Quote from: Icarus on June 24, 2013, 07:30:34 pmBuy from a legitimate distributor instead of eBay.

author: marshallh
author_rank: Unknown
timestamp: June 24, 2013, 08:32:40 pm
content: BTW it is possible to get counterfeits from Digikey. Luckily they're only jellybeans parts. Obviously once you let digikey know they'll make it right, but it's not impossible.

author: madires
author_rank: Super Contributor
timestamp: June 24, 2013, 08:46:50 pm
content: Quote from: Icarus on June 24, 2013, 08:10:32 pmSell them as rare counterfeits to collectors for 10 times the price you paid

author: Corporate666
author_rank: Unknown
timestamp: June 24, 2013, 08:47:00 pm
content: The problems of counterfeit components are not always immediate. I had some boards assembled in China and they substituted my National Semi LM317 regulators for "Chinese market" brand. Over the course of 3-4 years, about 80% of them failed in the field. They worked fine initially... but it was years down the road the problems surfaced.

author: ben_r_
author_rank: Frequent Contributor
timestamp: June 24, 2013, 09:06:15 pm
content: If it sounds too good to be true..... It probably is.

author: madires
author_rank: Super Contributor
timestamp: June 24, 2013, 09:17:50 pm
content: Quote from: Corporate666 on June 24, 2013, 08:47:00 pmI heard of similar experiences. The Chinese assembler replaced some expensive chips with counterfeits and sold the genuine ones for additional profit :-( Do they simply think that the counterfeit chip is as good as any other chip and take the opportunity to make some bucks extra or do they cheat on you deliberately?

author: Monkeh
author_rank: Super Contributor
timestamp: June 24, 2013, 09:44:30 pm
content: Quote from: madires on June 24, 2013, 09:17:50 pmThe latter. Don't ever think they're stupid, they've made a living off this sort of behaviour for a while now.

author: Rick Law
author_rank: Super Contributor
timestamp: June 24, 2013, 10:03:36 pm
content: I don't mind generics, but I don't like counterfeit.I got generic parts on eBay often and they are sold as such. I know they are no names and I am willing to take the risk for the lower price. I have not (to my knowledge) got counterfeit - one that is no-name but pretends to be some high value brand.Playing around as a hobbyist, I don't need high quality parts that lasts 10 years. As long as they are truthful about it being generic. Even while generics are without data-sheet highlighting the difference, I know they are generic and don't hold them to the performance of the tolerance of the "original".

author: c4757p
author_rank: Super Contributor
timestamp: June 24, 2013, 10:08:14 pm
content: Quote from: Rick Law on June 24, 2013, 10:03:36 pmWatch out for that one. Lots of hobbyists build themselves simple bits of gear that last years and years.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: June 24, 2013, 11:11:35 pm
content: Quote from: Icarus on June 24, 2013, 08:10:32 pmHmm, if you don't have test how did you find out they are fake

author: Corporate666
author_rank: Unknown
timestamp: June 25, 2013, 12:14:07 am
content: Quote from: madires on June 24, 2013, 09:17:50 pmIt only happened to me once... it was the first time I had boards assembled in China. It used several chips, a bunch of LED's and some passives. They advertised on their website that they could get the passives, but the salesman also said they could get some of the chips as well. Their price on the LM317 was amazingly low. The salesman described it almost like some kind of stock market system in China for chips... where anything could be purchased. I didn't know about Chinese counterfeit parts at the time, so I think I told them that as long as it was a known brand name, I was happy to use those parts.We had about a 5% failure rate upon receipt... but over time, about 80%.The weird thing is that when we started getting parts back, the mode of failure was actually the leads of the chips corroding and losing connection. This was before lead free, too. It was like the leads were contaminated with something and corroded on their own. If we scraped the legs down to copper, we could re-solder and jury rig the part into working.The main problem of course was the massive cost associated with shipping costs + labor to get all those boards back and rework them. Plus it pissed off a lot of customers.Now, I always either source the parts myself and send them, or I have them drop shipped right from Digikey China to their shop. I am very clear that they are only to use my parts, etc, etc. I haven't had a problem with them outright cheating me after I've given those instructions, but I'm sure we all know that business culture in China is "if you can get away with it, do it. If you can't get away with it, do it anyway and claim ignorance later".

author: Psi
author_rank: Super Contributor
timestamp: June 25, 2013, 12:57:15 am
content: I posted this a few days ago which turned out to be a counterfeit MAXIM chiphttps://www.eevblog.com/forum/projects/max7456-osd-chip-seems-unstable-when-cold/msg251370/#msg251370

author: Unknown
author_rank: Unknown
timestamp: June 25, 2013, 12:59:35 am
content: Ah, Rick, that articulated the doubt I was having, Generic vs. counterfeit. If they're not claiming it's a name brand, then what room does one have to complain when it's of inferior quality? It's only a problem if they claim it is a name brand but it's one of said generics.I think generics are really useful for prototyping. They let me get my component stash up without spending too much. Anything for production... not a chance, I'm going to digikey.

author: cthree
author_rank: Frequent Contributor
timestamp: June 25, 2013, 05:11:17 am
content: It's pretty simple really. Buy from an authorized distributor: Digikey, Mouser, Newark/Element 14, NuHorizons, Avnet, Arrow, Future (did I miss one?). That will ensure that you get 100% genuine parts. You will never, ever get a fake part from any of these distributors.

author: amyk
author_rank: Super Contributor
timestamp: June 25, 2013, 11:06:31 am
content: Quote from: Corporate666 on June 25, 2013, 12:14:07 amThat sounds more like bad storage than fake parts... an internal failure with no outward signs is more common for the latter.

author: Icarus
author_rank: Regular Contributor
timestamp: June 25, 2013, 11:10:15 am
content: Quote from: Alexei.Polkhanov on June 24, 2013, 11:11:35 pmLM317 is supposed to have over current and over temperature protection.But mine "special editions" are burning at 100mA (No overcurrent no overtemp (40C))

author: Rick Law
author_rank: Super Contributor
timestamp: June 25, 2013, 04:09:19 pm
content: Quote from: duskglow on June 25, 2013, 12:59:35 amI actually think, the best way to stop counterfeit is to encourage generic by low cost license.- If the real thing from the authorized dealer is $10- And a licensed-generic is $6I am not sure if I am typical, but in my view: The licensed-generic set a ceiling price for the suspected-counterfeit. If cost is a pressure, I go with the licensed generic for $6 than to buy something with suspicion for $8. In the process, the original designer also get some license royalty dollars. The more generic licensed manufacturer, the more "natural barrier" there is for those who wants to make a fake one.

author: mariush
author_rank: Super Contributor
timestamp: June 25, 2013, 04:33:39 pm
content: So now you gave those guys a reason to say "why are you offended/bothered that I erased the markings and labeled it as original one, after all it's a licensed generic so it MUST be the same circuit inside, right?"I don't know, maybe a good idea would be to engrave with laser a qr code which contains some encrypted data. that along with the serial on the chip gets entered on manufacturer's site and you know. (the serial plus some secret code only the manufacturer would know decrypts the data inside)or at least the manufacturer could say to you 'hey, the serial and qr code match, but this particular qr code (the encrypted data in it) was entered on the site by this many people so you probably have a fake chip"but this won't work with super tiny chips and adds a few cents to production not to mention the hardware to maintain such validation system.

author: edavid
author_rank: Super Contributor
timestamp: June 25, 2013, 05:49:53 pm
content: Quote from: Rick Law on June 25, 2013, 04:09:19 pmThere's no need for this. Unauthorized second sources are legal as long as you don't copy the masks, and there aren't any enforceable patents. Anyone can make an LM317 as long as they do their own layout.

author: Corporate666
author_rank: Unknown
timestamp: June 25, 2013, 06:21:19 pm
content: Quote from: amyk on June 25, 2013, 11:06:31 amCould be - but the National Semi logo was definitely "off" - blurry and off-sized vs crisp and clear on my NatSemi parts from Digikey. Quality of the epoxy case was pretty bad too... smooth and shiny vs. NatSemi which was slightly textured. I'm pretty sure these parts were fake.

author: SeanB
author_rank: Super Contributor
timestamp: June 25, 2013, 06:35:06 pm
content: Probably fake parts made from off spec leadframes and dice from a fab that were QC rejected, but which wound up being assembled by the third shift. Passed the more relaxed spec test of " did it blow up, OK ship that batch" and found it's way into the market.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: June 25, 2013, 08:20:54 pm
content: Quote from: Icarus on June 25, 2013, 11:10:15 amPlease share schematics, at least part of schematics that interfaces LM317 or schematics that you use for testing. I am just curious what capacitor values you used? What type of protection diode you have? What is input voltage? What is your load like? Inductive? When do you expect overtemp to kick in, at 40C? I am not sure, but I think overtemp protection is not universally available feature in LM317.

author: c4757p
author_rank: Super Contributor
timestamp: June 25, 2013, 08:24:55 pm
content: Every LM317 datasheet lists overtemperature and overcurrent protection. Perhaps the One Hung Low 317 has a datasheet that does not, but then it's not really compatible with theproper(LM = Nat Semi) LM317, now is it?

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: June 25, 2013, 08:52:27 pm
content: Quote from: c4757p on June 25, 2013, 08:24:55 pmThis Data Sheet from National Semi does not mention Overtemp protection at all:http://physics.gac.edu/~huber/classes/phy270/SpecSheets/LM317.pdf.One from Unisonic does, but then it is "internal" overtemp which you may not be able to measure accurately by measuring temp of the package. That temperature itself is greatly varies with package type - see picture.

author: c4757p
author_rank: Super Contributor
timestamp: June 25, 2013, 08:57:06 pm
content: Quote from: Alexei.Polkhanov on June 25, 2013, 08:52:27 pmQuoteQuoteCtrl-F, "thermal" - first thing it found.

author: c4757p
author_rank: Super Contributor
timestamp: June 25, 2013, 08:58:47 pm
content: Quote from: Alexei.Polkhanov on June 25, 2013, 08:52:27 pmTry again, and this time readallthe symbols in that table. Hint: /W

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: June 25, 2013, 09:02:34 pm
content: Quote from: c4757p on June 25, 2013, 08:57:06 pmYes, I guess it is same as Internal over temperature protection.

author: Unknown
author_rank: Unknown
timestamp: June 25, 2013, 09:06:24 pm
content: There are other ways to kill an LM317, for example reverse current, which is why a reverse biased diode across the regulator is required for large(ish) output caps.

author: Rick Law
author_rank: Super Contributor
timestamp: June 25, 2013, 10:45:49 pm
content: Quote from: c4757p on June 24, 2013, 10:08:14 pmYou may be right. So far, I have not done anything that is worth keeping. I have just been poking around. The most ambitious thing I have done so far is just a simple home-made Arduino UNO work-alike board - purposely done "from scratch" without consulting the "original" schematic so I can learn. Not much to that, but I now that I got it working, I may keep that one for a bit.

author: peter.mitchell
author_rank: Super Contributor
timestamp: June 26, 2013, 12:17:49 pm
content: A quick way I have found out about buying cheap components is to buy a legit one from digikey, crack open the package, then compare with the cheap one to see how big the die is, positioning, ect.

author: madires
author_rank: Super Contributor
timestamp: June 26, 2013, 12:51:32 pm
content: Quote from: Rick Law on June 25, 2013, 10:45:49 pmWith the years you'll pile up a nice collection :-) Several of my selfmade electronics are 20+ years old. There are things as a simple transistor tester, a signal generator (XR2206, very popular back then), several audio amps, home automation and modified/enhanced bought stuff. The sunblind control (opamp) outlived several sunblinds already, only had to replace a relay some years ago. Sometimes when I have to service my old stuff I'm astonished about PCBs made with an etch-resistant pen still working fine, no corrosion and nobody harmed by an electric shock :-)

author: JackOfVA
author_rank: Unknown
timestamp: June 26, 2013, 05:48:23 pm
content: I've seen an inverse problem; Chinese transistors better than the original parts that cause existing designs to fail.Specifically, 2N5109 parts from Motorola had an ft around 1.2 GHz and typical measured HFE around 50 or 60. These worked fine in a PCB layout (broadband amplifier up to 30 MHz). When Motorola spun its semiconductor business off to ON Semiconductor, the 2N109 was terminated and about all the new production these days is from Central Semiconductor in China.Within the last couple years, these transistors seem to have transitioned to a new die and/or process because the HFE is now 120-180 and ft seems to have increased to well above a couple GHz. Increased HFE isn't that much of a problem, but the increased ft makes the existing PCB layout extremely twitchy in terms of parasitic oscillations.

author: Rick Law
author_rank: Super Contributor
timestamp: June 26, 2013, 09:17:50 pm
content: Quote from: madires on June 26, 2013, 12:51:32 pmI can see that! Something to look forward to years from now. That could be kind of fun. I better stop smoking if I want to be around 20+ years from now...

author: richard.cs
author_rank: Super Contributor
timestamp: June 27, 2013, 08:17:58 am
content: Quote from: cthree on June 25, 2013, 05:11:17 amIt's less likely, and they'll refund you if it happens, but it does happen. For something work-related we had BFS20s from Farnell that were really some kind of audio frequency transistor. No idea what but they had a parasitic diode between c and e and the dies looked totally different when x-rayed. Externally they looked perfect, it's possible it was a manufacturing screwup and something got mislabelled or they were fakes.

author: Rick Law
author_rank: Super Contributor
timestamp: June 28, 2013, 09:53:11 pm
content: Quote from: amyk on June 25, 2013, 11:06:31 amA thought just occur to me. It may not be the part at all but the installation. It could be the solder - perhaps plumber's solder which is acid based. That kinds of solder will eat the join after a while. As to why just a specific part instead of all parts... No idea.

author: SeanB
author_rank: Super Contributor
timestamp: June 29, 2013, 07:58:29 am
content: Quote from: JackOfVA on June 26, 2013, 05:48:23 pmYou probably have a totally different device there rebranded as the old one. As it meets the specs, and then a lot more, they are using it, but it really should be marked as another device or as a near equivalent. You probably should look and see what device they are actually using so you can get the proper datasheets and rework your application to handle it.

author: vk6zgo
author_rank: Super Contributor
timestamp: June 30, 2013, 04:44:45 am
content: You can definitely be caught out by changes in specs.I was working on a "in house" made Transmitter remote control which used several monostables to provide delays.The RC time constant was quite long,but the NS book we worked from when it was made said that that part was quite happy with such time durations.I mislaid several of the monos,& so replaced them with the same part number ex stock.The thing became intermittent!!It turns out that NS had decided to optimise this device for shorter time constants,with the result that it would sometimes "drop out" before the full duration in our application.They suggested another IC which was designed for longer time constants,& which was a plugin replsacement.We fitted them & all was well.No,I can't remember the part numbers,it was too long ago!

author: amyk
author_rank: Super Contributor
timestamp: June 30, 2013, 10:14:15 am
content: Quote from: edavid on June 25, 2013, 05:49:53 pmEven the layout is only protected for 10 years in the US, so the layout of any ICs made before 2003 is, if there's no other copyrights/patents, effectively public-domain.

author: serik5000
author_rank: Contributor
timestamp: July 01, 2013, 12:35:44 pm
content: I am curious, do they counterfeit only simpler analog and basic ICs? Is it possible to get fake LSI and VLSI devices such as Altera FPGAs? I noticed a few Chinese sellers offering them for almost 50% of the US price which is by the way, seems to be fixed in the US (the same regardless of distributor).Does it mean China is selling fake copies or is it just Altera screwing US customers by dictating deliberately higher prices on US market?

author: pmcouto
author_rank: Unknown
timestamp: July 01, 2013, 01:25:41 pm
content: Hi serik5000,There are 2 different issues:-Counterfeit components-“Grey market” componentsCounterfeit components are a real plague. These are manufactured by some obscure fabs, violating many copyrights and often producing, at best, inferior quality parts.But things can easily become very nasty:I’ve seen more than once components (transistors and ICs) that did not have any silicon die inside!“Grey market” components are a whole different story. These are legit components, normally coming from excess inventory or production leftovers that are sold at scrap prices.There are a lot of dealers specialized in this “market”, many times selling the parts at a fraction of its real cost.Last but not least, there are also some Chinese dealers selling components recovered from scrap PCBs. Obviously, these are also legit parts and can be sold well below the normal market price. Some of these dealers advertise these parts as “used” but there are also some not honest enough to inform the customers about this fact…Regards,Pedro Couto