What do you know about fake chips. - Page 1
Forum section: electronics / general

author: sfiber
author_rank: Regular Contributor
timestamp: July 02, 2014, 01:04:13 pm
content: I have ordered 25 pcs lm324n from aliexpress and it came today.its look like;but its should seem like this;I tested it to check to circuit what's going on in operation and it's actually work well.what do you think about this.its fake or not.I didnt see this puntos on any of the other of ti chips.

author: Psi
author_rank: Super Contributor
timestamp: July 02, 2014, 01:06:47 pm
content: Probably not legit, but its possible the die maybe the same as the real chip and from the same factory.Sometimes there are excess production runs (fab makes more die's than they're supposed to)Or die's that failed QCBut more likely it's another companies LM324N that has been labeled to try and sell at a higher price.

author: dannyf
author_rank: Super Contributor
timestamp: July 02, 2014, 01:07:13 pm
content: I was given some TL071 where the offset pins don't work. Otherwise, it is fine.I am actually surprised that people would fake such low cost chips - given how little the dies cost, why bother?

author: Psi
author_rank: Super Contributor
timestamp: July 02, 2014, 01:13:15 pm
content: With a lot of it they don't "set out" to fake the chip.China is all about reusing things instead of throwing them away.You have a pile of worthless unused semiconductor die's that failed QC because they were 5% out of spec and your boss tells you to get rid of them.You have access to a DIP capping machine, so you might as well feed them all through it and sell the chips for a few cents each.

author: sfiber
author_rank: Regular Contributor
timestamp: July 02, 2014, 01:24:35 pm
content: Quote from: Psi on July 02, 2014, 01:13:15 pmif as you say,they write(laser) company logo and part number after QC.Because that font it is not familiar to me.

author: dannyf
author_rank: Super Contributor
timestamp: July 02, 2014, 01:30:45 pm
content: I don't know if there is any value trying to figure out if it is fake or not, if the chip actually works well as you say.I would worry about it if it didn't work well.

author: free_electron
author_rank: Super Contributor
timestamp: July 02, 2014, 01:35:24 pm
content: That looks like the samsung font. The ti logo is way off in shape.Probably a KIA324 that is relabeled.

author: Kjelt
author_rank: Super Contributor
timestamp: July 02, 2014, 01:38:30 pm
content: look at the bottom for country of production?I had some LT1785's from Ebay and was very concerned if they were legit, so bought another few from Farnell and compared them under a microscope and scratching the upper surface. They looked the same apart from the production codes.

author: sfiber
author_rank: Regular Contributor
timestamp: July 02, 2014, 01:39:03 pm
content: @dannyf I have 24 pcs other.I think few of them may have a problem.

author: dannyf
author_rank: Super Contributor
timestamp: July 02, 2014, 02:19:05 pm
content: Maybe it is cheaper to buy from a more expensive / reputable source.

author: sfiber
author_rank: Regular Contributor
timestamp: July 02, 2014, 03:46:27 pm
content: yes dannyf I agree to you competely.I am going to use local companies that I trust,in IC shopping.

author: wraper
author_rank: Unknown
timestamp: July 02, 2014, 08:31:22 pm
content: Once I bought a few Toshiba TB6560AHQ stepper motor drivers on ebay from two sellers. They looked identical. Thankfully I checked them with multimeter first. So I figured out that one seller sold me fakes because GND pins were totally wrong and heatsink pad was connected with completely different pins. But package was 100% identical. So I started googling and according to the datasheet figured that they were relabeled TA8435 stepper drivers. No wonder that package was the same as they also are Toshiba parts. As they are laser labeled, I think they took older ones with paint marking, cleaned it with solvent and lasered new marking onto them. Funny thing that TA8435 was more expensive on ebay. Maybe they just needed more TB6560AHQ that day.

author: wraper
author_rank: Unknown
timestamp: July 02, 2014, 08:45:39 pm
content: Quote from: dannyf on July 02, 2014, 01:30:45 pmYou now, it is much better if they just don't work so you can just throw them in the trash. Otherwise a thought that they are crap bothers you but it's a pity to throw them away, because you're not sure as they might be a legit parts. Or they can just fail on you later or cause strange behavior you can't explain.

author: dannyf
author_rank: Super Contributor
timestamp: July 02, 2014, 09:40:22 pm
content: QuoteDo they function as TA8435?QuoteNow, that makes perfect economic sense,.I have to say that I don't understand those fake parts sold via ebay. Unless the buyers don't complain or have no way of knowing, it makes no sense for someone try to sell fake parts over ebay.I do know that rather than "fake" / non-functioning parts, there are parts that are re-packaged: take Part A soldered in a recycled circuit and take the die out and re-package it onto a new body with new leads, etc. and sell them.In those cases, they tend to be limited to higher priced, higher volume parts.LM324? How do you make any money there?

author: Stonent
author_rank: Super Contributor
timestamp: July 02, 2014, 09:49:21 pm
content: I did some googling and this one would definitely concern me.The lettering seems to go up and down.On yours, given that it is 30 years old the package could have changed significantly since then.

author: Stonent
author_rank: Super Contributor
timestamp: July 02, 2014, 09:57:57 pm
content: http://www.ebay.co.uk/itm/10-pcs-LM324N-LM324-324-Low-Power-Quad-Op-Amp-IC-DIP-US-Seller-/281368889910?pt=LH_DefaultDomain_0&hash=item4182e48a36This seller is selling a chip that looks exactly like yours.

author: wraper
author_rank: Unknown
timestamp: July 02, 2014, 10:03:17 pm
content: Quote from: dannyf on July 02, 2014, 09:40:22 pmDidn't check if they function properly as it would take too much time to check that, you can't just plug them into the breadboard. But considering HZIP25 package with smallest details matching Toshiba part, complete match of the power pins and lack of similar ICs made, I'm pretty sure they would. Actually I kept them, maybe sometime will wave a chance to test.

author: wraper
author_rank: Unknown
timestamp: July 02, 2014, 10:38:25 pm
content: BTW package of that LM324 don't look at all like TI and new at all. It's more like package made 20-30 years ago. I also see shiny leads, aren't there excessive solder on them? And anyway that is a fake considering crappy TI logo and crappy marking at all.Oh, remembered one more fake IC experience on ebay. So once I ordered 2pcs of ST M2732A FI on ebay. A bit later realized that I may need more, so ordered 2 extra from the same seller. So then they arrived, 2 of them were exactly like on this picture, including date code:But two another were with large die like AMD AM2732 but had exactly the same marking including the date code, font and overall look:So I used them all but programmed AM2732 with 25V Vpp instead of 21V. Btw programmer auto recognized first as M2732A, but coudn't recognise second. So my conclusion was that first ones were genuine M2732A with fake mark (newer date code). But second ones were really old 80's NOS AM2732. There were no any usage (socket) signs on the pins. But who knows, they might be used as well.

author: Richard Head
author_rank: Frequent Contributor
timestamp: July 03, 2014, 06:51:43 am
content: Why do you guys order this shit from ebay? Just buy the proper stuff from a legit supplier such as Farnell/EBV etc.

author: marshallh
author_rank: Unknown
timestamp: July 03, 2014, 07:20:34 am
content: Because of the tinned leads it's definitely a pull, and probably remarked too. No TI part of that vintage was marked like that.Seriously, don't buy ICs off ebay unless you know what you're doing. Not sure why everyone has to learn this lesson over and over again.

author: abaxas
author_rank: Regular Contributor
timestamp: July 03, 2014, 07:53:47 am
content: Why did you buy it from a 'shop' that sells everything?There are plenty of more specialized electronics sellers on alibaba/aliexpress who usually give a better service and you get what you pay for.I still wouldn't buy anything of value or electrolytic caps from china... but the rest is fine.

author: wraper
author_rank: Unknown
timestamp: July 03, 2014, 08:32:00 am
content: Quote from: Richard Head on July 03, 2014, 06:51:43 amBecause you can't get some parts there or they cost astronomic price. For example you cannot buy both ICs I mentioned at Farnell.Quote from: abaxas on July 03, 2014, 07:53:47 amThey are not much better. Should expect crap from everyone.

author: abaxas
author_rank: Regular Contributor
timestamp: July 03, 2014, 08:45:15 am
content: Maybe Ive' been lucky and have only one issue out of >30 purchases.

author: abaxas
author_rank: Regular Contributor
timestamp: July 03, 2014, 08:52:46 am
content: Quote from: marshallh on July 03, 2014, 07:20:34 amYou have to remember that lots of this 'shit' isn't available anymore so you have to rely on the 2nd hand/grey markets.

author: sfiber
author_rank: Regular Contributor
timestamp: July 03, 2014, 11:22:31 am
content: Actually there was a reason to buy ic from china.my first ic shopping, I ordered 2 pic18f4550 and I gladded with chips because they are originial and cheap.I ve know a story of fake pic16f887.first he tried to code with originial ic that bought from distributor and in this code there is an adc calculation.then code is tried with fake one and you cant believe to adc value errors.

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 12:35:10 pm
content: QuoteWell, you often pay dearly for low prices. (Un)fortunately, people continue to make the same mistakes over and over.

author: abaxas
author_rank: Regular Contributor
timestamp: July 03, 2014, 01:07:49 pm
content: Quote from: dannyf on July 03, 2014, 12:35:10 pmIn one sentence you have managed to destroy the whole of car industry in the states.Cheap / nasty != bad.

author: amyk
author_rank: Super Contributor
timestamp: July 03, 2014, 01:39:27 pm
content: Quote from: sfiber on July 03, 2014, 11:22:31 amMicrochip sells untested PICs under a different part#, intended for large manufacturers who test them for the application, so I wouldn't be surprised if it was one of those remarked.I've written a bit about this before.

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 01:46:50 pm
content: QuoteTrue, on particularly parts or brands.Untrue, statistically speaking.

author: all_repair
author_rank: Frequent Contributor
timestamp: July 03, 2014, 03:02:53 pm
content: http://tronixstuff.com/2013/05/16/the-max7219-led-display-controller-real-or-fake/

author: sfiber
author_rank: Regular Contributor
timestamp: July 03, 2014, 06:35:56 pm
content: lets think about chinese fakers.First they going to buy lm317 to 1 dollar and then erase the part numbers etc.Then they write lm338 with laser and they sell it to 3 dollars.I dont know they have same dimensions but I know that people dont look at the datasheets for dimensions,always.

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 07:30:42 pm
content: QuoteRather than wasting your time on such hypotheticals and your money on fake parts, you could have bought from a legit channel and enjoyed building your circuits.You are too poor to buy cheap parts.

author: sfiber
author_rank: Regular Contributor
timestamp: July 03, 2014, 09:03:50 pm
content: I think some of them dont want to understand the point of this topic.Noone recommend to buy chips from ebay or aliexpress but they sell and someone have bought theese even a time like me.Actually I bought chips from my local seller and it has a distributor like farnell(I dont know to which one).

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 09:08:33 pm
content: It is a question of expectation (and wisdom,).If you buy from a shitty place, you should expect shitty products / services.If you buy from a shitty place repeatedly, you should wise up, hopefully quickly.The only reason those shitty places can survive is that there are people foolish enough to buy from them, especially if they buy repeatedly.If you want to kill those places, buy from a place that sells good parts and treats you like a customer.

author: sfiber
author_rank: Regular Contributor
timestamp: July 03, 2014, 09:24:24 pm
content: I know what s the point of buying from distributor but if you live in east europe there are some exception about system.Only if you purchase over 150 €,you can get rid of from domestic and overseas shipping.Otherwise you have to pay them to.Let say you buy chips over 150 €,then you have to tussle with taxes.

author: all_repair
author_rank: Frequent Contributor
timestamp: July 03, 2014, 09:37:09 pm
content: Quote from: AcHmed99 on July 03, 2014, 08:07:04 pmHe was partly doing it for curiousity, and partly for the fun of it, I think.I had an opportunity to work in an electronics retail shop when there were many semiconductor factories here. I was asked to do a lot of go/no go test for unmarked transistors which were dirty and looked like from dumpsters. Later I found out these parts were not really fake, but rejected parts from the factories and meant to be disposed of. Somewhere from the factories to the landfills, or even after they were buried, they were savaged and sold to these shops. Of course, these parts were later made over to the latest hot selling number.So if the fake has not so nice pins, they are likely to be better than those fake with perfect pins.

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 09:41:00 pm
content: Quotethen tussle with taxes: it is better to pay more for parts you can use than to pay a little bit less for parts you cannot use.I understand that from time to time, you may need to buy knowingly from a shitty place. I don't understand that you are surprised that you are getting shitty parts / services from a shitty place - to me, it is par for the course.