5 ms·

Those AliExpress chips may not be genuine. Buying from unauthorized distributors has always been risky, and some companies (especially Chinese ones) have been k

by nickff 6y ago

Those AliExpress chips may not be genuine. Buying from unauthorized distributors has always been risky, and some companies (especially Chinese ones) have been know to stamp blank or generic parts with whatever part number you're looking for. The really tricky vendors will put a few (10-50) genuine parts at the beginning and end of a reel (to pass validation testing), with defective or fake ones in between. Non-genuine parts may also be lower-spec versions of what they are labelled as (like a slower microcontroller or a higher offset op-amp).

Syonyk 6y ago
For a fun set of reads on this ("Label the chips as what the buyer wants regardless of what they actually are") from a decade ago, Sparkfun got some "fake" ATMega 328p chips in that, in fact, were nothing remotely resembling an ATMega 328p. In the words of someone after they'd puzzled out the puzzle, "...so it looks like that die in the picture is pre-release engineering material. Where the hell did you find that?" https://www.sparkfun.com/news/350 https://www.sparkfun.com/news/350 https://www.sparkfun.com/news/364 https://www.sparkfun.com/news/364 https://www.sparkfun.com/news/384 https://www.sparkfun.com/news/384 https://www.sparkfun.com/news/395 https://www.sparkfun.com/news/395
- Scoundreller 6y ago
  A proper scale should be able to detect weak effort fraud like this.
  - Syonyk 6y ago
    A proper scale can detect all sorts of weak effort fraud. Years back, I talked to someone who had done some analysis on some of the "fake silver/gold" bars floating around places (I think they were common on Silk Road for a while?). Apparently some of the people faking metal bars didn't actually bother learning what a "Troy Ounce" was. There was a "10 oz" bar that was 10 ounces - 283.5 grams. Except, in metals, "oz" means Troy Ounce - so it should have been 311 grams. You could literally feel that it was light if you were used to dealing with metals.
    - dan-robertson 6y ago
      I suspect it wasn’t really trying to defraud people who know what a Troy Ounce is. I’d find it believable if people thought fake bars at 311g were frauds for not weighing 10oz.
- routerl 6y ago
  This was a great read, thanks!
- jandrese 6y ago
  I'm guessing it's a sample run and the company realized there was a bug in the silicon and told the fab to destroy the rest of the samples. Instead someone at the fab set them aside for the future when they need some raw material to scam people with. I find it strange that whoever decided to do this kept the correct datecode on the packaging. Presumably they didn't label them as ATMega 328s until the order came in, it would have been trivial to change the datecode to something reasonable for that chip.
- danmur 6y ago
  That's super interesting, thank you!
swiley 6y ago
This is why buying chips off amazon isn't always a great idea.
segfaultbuserr 6y ago
It's a gray market. Sometimes, I mean sometimes, these chips are real and they usually come from a "leak" in the supply chain - unauthorized resales by small vendors, or "unwanted" surplus from a previous order or production run. Usually they exist only in small quantities and are stored and handled in unknown conditions, it's not something you want to use in production. But it explains why the AliExpress vendors always have some components when major distributors are out of stock (e.g. You can do it too - just order all the remaining stock of a rare chip from Digikey and put them on eBay...) For example, I heard that a common practice in Shenzhen is selling reels of genuine components, but the "lot number" (serial number) on the labels are removed, so the manufacturers cannot trace these unauthorized resales back to the source. Another example, in a personal hobby project I needed to use a specialized controller that is not available on the public market, but a AliExpress vendor has them, it's likely surplus from somewhere. > I can see those chips available in their thousands on aliexpress and similar sites for 10x the price The quantity is not always real, sometimes they just put a random number here. And even when it's accurate, the sales occur via various online and offline channels simultaneously. --- Disclaimer: It's extremely risky to order components from an unknown source, I do not endorse doing it. And my hypothesis on their origins is my speculation, so take a grain of salt.
- Badfood 6y ago
  Random story... I bought some resistor kits from aliexpress. I noticed the few I used were super accurate. So I tested a bunch. They were all accurate to, not sure exactly but let's say 0.1% ish. I went and measured a bunch of 1% ones from digikey,and they were around 0.5 to 1%. I guess they were tight tolerance ones that made it into a ultra cheap smd kit.
  - Scoundreller 6y ago
    I like to think we’ve gotten so good at making something as basic as a resistor that modern/established manufacturers are so consistent there practically is near-zero tolerance for error.
  - segfaultbuserr 6y ago

by nickff 6y ago

Syonyk 6y ago

For a fun set of reads on this ("Label the chips as what the buyer wants regardless of what they actually are") from a decade ago, Sparkfun got some "fake" ATMega 328p chips in that, in fact, were nothing remotely resembling an ATMega 328p. In the words of someone after they'd puzzled out the puzzle, "...so it looks like that die in the picture is pre-release engineering material. Where the hell did you find that?" https://www.sparkfun.com/news/350 https://www.sparkfun.com/news/350 https://www.sparkfun.com/news/364 https://www.sparkfun.com/news/364 https://www.sparkfun.com/news/384 https://www.sparkfun.com/news/384 https://www.sparkfun.com/news/395 https://www.sparkfun.com/news/395

Scoundreller 6y ago
A proper scale should be able to detect weak effort fraud like this.
- Syonyk 6y ago
  A proper scale can detect all sorts of weak effort fraud. Years back, I talked to someone who had done some analysis on some of the "fake silver/gold" bars floating around places (I think they were common on Silk Road for a while?). Apparently some of the people faking metal bars didn't actually bother learning what a "Troy Ounce" was. There was a "10 oz" bar that was 10 ounces - 283.5 grams. Except, in metals, "oz" means Troy Ounce - so it should have been 311 grams. You could literally feel that it was light if you were used to dealing with metals.
  - dan-robertson 6y ago
    I suspect it wasn’t really trying to defraud people who know what a Troy Ounce is. I’d find it believable if people thought fake bars at 311g were frauds for not weighing 10oz.
routerl 6y ago
This was a great read, thanks!
jandrese 6y ago
I'm guessing it's a sample run and the company realized there was a bug in the silicon and told the fab to destroy the rest of the samples. Instead someone at the fab set them aside for the future when they need some raw material to scam people with. I find it strange that whoever decided to do this kept the correct datecode on the packaging. Presumably they didn't label them as ATMega 328s until the order came in, it would have been trivial to change the datecode to something reasonable for that chip.
danmur 6y ago
That's super interesting, thank you!

swiley 6y ago

This is why buying chips off amazon isn't always a great idea.

segfaultbuserr 6y ago

It's a gray market. Sometimes, I mean sometimes, these chips are real and they usually come from a "leak" in the supply chain - unauthorized resales by small vendors, or "unwanted" surplus from a previous order or production run. Usually they exist only in small quantities and are stored and handled in unknown conditions, it's not something you want to use in production. But it explains why the AliExpress vendors always have some components when major distributors are out of stock (e.g. You can do it too - just order all the remaining stock of a rare chip from Digikey and put them on eBay...) For example, I heard that a common practice in Shenzhen is selling reels of genuine components, but the "lot number" (serial number) on the labels are removed, so the manufacturers cannot trace these unauthorized resales back to the source. Another example, in a personal hobby project I needed to use a specialized controller that is not available on the public market, but a AliExpress vendor has them, it's likely surplus from somewhere. > I can see those chips available in their thousands on aliexpress and similar sites for 10x the price The quantity is not always real, sometimes they just put a random number here. And even when it's accurate, the sales occur via various online and offline channels simultaneously. --- Disclaimer: It's extremely risky to order components from an unknown source, I do not endorse doing it. And my hypothesis on their origins is my speculation, so take a grain of salt.

Badfood 6y ago
Random story... I bought some resistor kits from aliexpress. I noticed the few I used were super accurate. So I tested a bunch. They were all accurate to, not sure exactly but let's say 0.1% ish. I went and measured a bunch of 1% ones from digikey,and they were around 0.5 to 1%. I guess they were tight tolerance ones that made it into a ultra cheap smd kit.
- Scoundreller 6y ago
  I like to think we’ve gotten so good at making something as basic as a resistor that modern/established manufacturers are so consistent there practically is near-zero tolerance for error.
- segfaultbuserr 6y ago