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Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

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Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#71

Post by bigiain »

as-j wrote: post #6

This affects temperature sensors/parts bought from un-official distributors like ebay or AliExpress, not digikey, farnel, etc. Perhaps I've been too lucky in my career and practiced EE for work, but who would you ever go to ebay instead of digikey?? Digikey certainly has a premium, but their speciality is small numbers/cut tape/etc and they have a small order size which makes them ok for hobby work, and I've used the…

You might not buy em from eBay/Alibaba - but the guy your contract manufacturer goes to might end up getting them from the same source as the eBay/Alibaba vendors do - either knowingly or unwittingly.

We ended up with 3 spools of counterfeit WS2812Bs that had cheapskated out on some data line capacitors on the die. Totally fucked the emitted RF noise levels compared to the same thing build with genuine ones, and intermittently flaked out when trying to run high speed data updates long-ish distance - the lights 6-7m and 40-50 leds from the controller weren't reliable...

Manufacturer and their supplier were very good at fixing things for us once the problem was discovered and attributed to bad components, but it was a very stressful lead to the xmas supply chain back then. (Then the entire company fell apart for different reasons, but the stress and expense of that incident was quite likely a strong contributor to those the triggering of those company-ending reasons... :shrug:)

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#72

Post by analog31 »

kregasaurusrex wrote: post #36

Trust in hardware supply chains when manufactring a PCB for a product can be quite fragile: when one component operates outside of spec, the entire device could be rendered useless. In the case of the DS18B20, the author states in the 'Warning' section that the primary way of determining counterfeit sensors is to check the ROM output compared to a known format. When counterfeit parts like this are added, it creates v…

If I recall correctly, FTDI took some well deserved heat, but quickly discontinued this practice.

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#73

Post by bigiain »

IgorPartola wrote: post #32
myself248 wrote: post #12

Earlier quoted context omitted.

I'd never expect to find these in official products from trusted brands, but off-brand crap? Oh yeah. DIY kits? Absolutely. The parts drawer at the makerspace? One hundred percent. So much stuff on eBay is free shipping, that's huge when you only need a few dollars worth of stuff. If I could convince Digi-Key to lick a 55-cent stamp when I need ten of something, instead of charging me $7 for shipping, I'd have a lot…

This. I buy a decent amount of hobby electronics from eBay and AliExpress because yes it is cheaper. When I need quality, Mouser, DigiKey, and McMaster-Carr are there for me. But the minimum $7-9 shipping is the main reason is forego them. I’d gladly pay 2x for small electronic components (vs directly from China options) if shipping wasn’t a problem.

Same. I read through this thinking "What, my team sensor on the data logger for my coffee grinder might be more than half a degree out? You know what? I totally don't care, and wouldn't have spent an extra 50 cents to get that much accuracy..."

I do have ethical qualms about supporting/funding "stolen IP", but then I've kinda got ethical qualms about the whole concept of IP anyway, and if you wanted to go hardline on IP compliance you'd probably have to avoid everything out of China (and everything that contains components out of China)... I wonder how often Apple get counterfeit components slipping through on Foxconn production lines, and how much effort they put into stopping it beyond extensive QA - which only ensures any counterfeits that make it through need to be close-enough to functionally equivalent to pass all the tests? The "test after" approach kinda pushes towards more IP infringement rather than less, since it's likely parts built from stolen designs would pass more often that parts reimplemented according to the spec?

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#74

Post by selectodude »

IgorPartola wrote: post #32
myself248 wrote: post #12

Earlier quoted context omitted.

I'd never expect to find these in official products from trusted brands, but off-brand crap? Oh yeah. DIY kits? Absolutely. The parts drawer at the makerspace? One hundred percent. So much stuff on eBay is free shipping, that's huge when you only need a few dollars worth of stuff. If I could convince Digi-Key to lick a 55-cent stamp when I need ten of something, instead of charging me $7 for shipping, I'd have a lot…

This. I buy a decent amount of hobby electronics from eBay and AliExpress because yes it is cheaper. When I need quality, Mouser, DigiKey, and McMaster-Carr are there for me. But the minimum $7-9 shipping is the main reason is forego them. I’d gladly pay 2x for small electronic components (vs directly from China options) if shipping wasn’t a problem.

That's actually how much it costs to ship stuff when it's not being exceptionally heavily subsidized by the utterly broken Universal Postal Treaty.

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#75

Post by mindslight »

metaphor wrote: post #68
mindslight wrote: post #33

Earlier quoted context omitted.

How else can you get anything from Maxim besides samples? (joke may be a decade out of date)

I understood that joke to mean, "Maxim components are so expensive that the grey market is about the only place the layman can afford them in more than 1-off prototype quantities." At least that was my experience 8 or so years ago when I made the mistake of purchasing a lot of 100 MAX7219 off eBay for $100 shipped from China...$1/ea was such a tempting deal to a younger, more naive self when these chips were selling…

No... there was a time when Maxim parts weren't really available through the major distributors. They had one of the most generous sample programs, but apart from that they seemingly wanted to draw you into some heavyweight direct sales process based around millions of parts per year. As the things I was designing were mostly aiming for quantities in the thousands, it made me not even bother considering their parts.

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#76

Post by LeifCarrotson »

robomartin wrote: post #58
kregasaurusrex wrote: post #36

Trust in hardware supply chains when manufactring a PCB for a product can be quite fragile: when one component operates outside of spec, the entire device could be rendered useless. In the case of the DS18B20, the author states in the 'Warning' section that the primary way of determining counterfeit sensors is to check the ROM output compared to a known format. When counterfeit parts like this are added, it creates v…

> This anti-consumer behavior on behalf of companies I strongly disagree with this. I see no way to rationalize that a company should be responsible for ensuring that counterfeit devices work correctly by releasing drivers that are tolerant of them or do not stop them from functioning. FTDI's products are the combination of their hardware with their drivers. Both are required in order to delivery functionality and re…

I agree that anyone who built a device and knowingly used a counterfeit FTDI chip deserved to be punished.

However, the FTDI debacle didn't punish those people, they're not the consumers. It punished end users who have no idea what an FTDI chip is or does or that one exists in the products they buy.

In your airliner microcontroller example, you have much more informed consumers. They could reasonably be expected to know what processor is in their hardware, and to want to validate it. That's not the same.

It would be more like a good packaging manufacturer finding that their packaging was being counterfeited and their proprietary plastic blend was somehow being leaked up the supply chain. If they changed their recipe to something toxic, but using good plastic internally, and when people started dying said "they should have bought potato chips packaged in genuine FoodSafeStuff bags". People don't know what their packaging is made from or who it's made by. They have no way to verify it prior to purchase, and even after purchase, it would take an expert to identify. And there's no customer loyalty based on the plastic bag, after the food manufacturer switches away from the counterfeit they won't be significantly harmed. But everyone who innocently bought those bags and got poisoned suffered real harm.

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#77

Post by bigiain »

fermienrico wrote: post #51
IgorPartola wrote: post #32

Earlier quoted context omitted.

This. I buy a decent amount of hobby electronics from eBay and AliExpress because yes it is cheaper. When I need quality, Mouser, DigiKey, and McMaster-Carr are there for me. But the minimum $7-9 shipping is the main reason is forego them. I’d gladly pay 2x for small electronic components (vs directly from China options) if shipping wasn’t a problem.

For any serious person trying to develop a little bit beyond hobby projects: Think about an hourly rate of $80/hour for yourself. If you have to spend an hour trying to fiddle with subpar shady parts, you've already paid for the shipping 8 times over. Also, it is painful to wait for these packages from China. Digikey ships same day and its at your door step in the morning (I overnight it) and if you use $7, it is usu…

> I can understand total hobbyist who cannot afford $7 shipping often. But even then, you can bundle all your parts and order once.

Or, like me, pretty much go "Meh, its counterfeits all the way down!" and frequently tack on a buck or twos worth of other "That's interesting looking, I might want one of those one day, I'll grab a few on this order" stuff when you're buying things you need for a current (hobby grade) project, so you've got a few boxes full of (hopefully sufficiently well enough labelled and documented" junk on-hand for the next random project idea... I bet I have a dozen or so "DS18b20"s here from that approach. I _think_ I could probably find then in under 10 minutes if I had an idea that needed one right now. Maybe... (Actually, I do have that idea. I want to put temp logging on a little LiPo battery that sits under a small solar panel to run an ESP32. I _think_ it's probably failing early because the whole thing gets too hot in the du5rect sunlight. Logging will confirm/deny that, and let me measure changes with insulation and/or fan cooling. Maybe I'll go hunt for one tonight...)

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#78

Post by bigiain »

ckocagil wrote: post #48
exmadscientist wrote: post #9

Earlier quoted context omitted.

Another professional EE here. I never expect random chips bought off AliExpress/eBay/Amazon/etc to work, much less be genuine. I do expect breakout modules and the like to work, though I don't expect them to contain genuine parts. (That implies I'd never source from these places when it's a critical function.) I'm always surprised when people expect grey-market crud to perform just as well as top-dollar stuff....

I do electronics as a hobby. I sometimes buy chips from very dubious shops in China for fun. Some of these sources are sketchy even by Taobao/Aliexpress standards. Then I decap the chip by boiling the package in acid and inspect the die under a microscope. More than half of them are genuine. I get some nice surprises because even the chips that I expect to be absolutely fake can turn out to be genuine. So far I've se…

> Some of these sources are sketchy even by Taobao/Aliexpress standards.

Links? That sounds fun...

Re: Your DS18B20 temperature sensor is likely a fake, counterfeit, clone

#80

Post by as-j »

bigiain wrote: post #71
as-j wrote: post #6

This affects temperature sensors/parts bought from un-official distributors like ebay or AliExpress, not digikey, farnel, etc. Perhaps I've been too lucky in my career and practiced EE for work, but who would you ever go to ebay instead of digikey?? Digikey certainly has a premium, but their speciality is small numbers/cut tape/etc and they have a small order size which makes them ok for hobby work, and I've used the…

You might not buy em from eBay/Alibaba - but the guy your contract manufacturer goes to might end up getting them from the same source as the eBay/Alibaba vendors do - either knowingly or unwittingly. We ended up with 3 spools of counterfeit WS2812Bs that had cheapskated out on some data line capacitors on the die. Totally fucked the emitted RF noise levels compared to the same thing build with genuine ones, and inte…

Yeah, that's what scares me. On the other hand...I do have to trust my CM for so much already. Trust is an interesting thing in business.
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