i won't buy chinise parts from aliexpress or ebay

[thm_w]

If you find out in time. Those attiny were made quite convincing. Unfortunately I did not compare of date/lot code on top and bottom as they should match (they did not). Found out only during testing after they were placed on 100-ish of boards. More than half of the boards consumed like 2mA more than normal, other consumed as they should. When I checked date code on the backside, it became clear that those which consumed more were made before 24A was even released.
Stepper drivers sat in my drawer a few years before I decided to actually use them.

I think most people here are building one or two boards. Anyone populating 100s of boards with parts from alix without thoroughly testing a few first is a bit reckless IMO.

Since I can read Chinese, I never had to buy from AliExpress, but I buy considerably large amount of parts from Taobao (10000+ CNY since this Chinese new year, which was extended to 2/16 for COVID19), and so far I've yet to find fake ones since I moved back to China last December.

Bought these and they were both fake, but that was to be expected (unobtanium part for pennies):
https://item.taobao.com/item.htm?id=35631303299
https://item.taobao.com/item.htm?id=544364491832
Some other regulator that can't handle ~30V.

[wraper]

Anyone populating 100s of boards with parts from alix without thoroughly testing a few first is a bit reckless IMO.

They were inspected under microscope upon receiving and a few tested. It's obvious all of them were working. I didn't know at that moment that Atmel prints date code on the back so did not focus on that. As I said, they were made pretty convincing.

[ozcar]

Around two years ago I bought 10 x LM311P from a Chinese seller on Ebay. Only got around to trying to use one something like 6 months later, and found that none of them worked. I turned up an old thread here dating back to September 2015 ( https://www.eevblog.com/forum/chat/fake-andor-mislabelled-lm311-)/ ), where somebody reported receiving what appeared to be LM358 marked as LM311. I checked the ones I had, and they too could have been LM358.

I was surprised by this. An LM358 (dual opamp) has no chance of working as an LM311 (single comparator with OC/OE output). Why bother to have any chip at all inside? And what is particularly attractive about doing this, that it had been happening for at least three years at the time?

Fast forward to the present. About a week ago I ordered 5 x LM311P from a local (Australian) seller - one with "good" prices, but not "ridiculously cheap". I received them only two days ago, and although the marking on them is slightly different to the dodgy ones I got before, these too appear to be mislabelled dual opamps.

I put in a return request yesterday, explaining the problem, and within 15 minutes I received a refund, but without any explanation. I see that the listing I purchased from is still up on Ebay, but items not currently available for purchase as it has been flagged "seller is away". None of their other listings has been flagged like that. The jury here has still to decide what this particular seller knew.

[Bud]

Buy from an industrial supplier and save yourself time and frustration. When you people will get that 

[dietert1]

And how will you proceed? The refund will by you 1.4 samples from mouser. Can't you get some free samples from Infineon?

Regards, Dieter

[SilverSolder]

with banana skins in the gearbox and differential to keep them quiet

One learns something new every day! 

Note, it only works for the duration of the test drive!  (Sawdust may last slightly longer!)

[nigelwright7557]

I bought in some Chinese solder for doing small pitch SMD 0.5mm
What a disaster it just barely melted and great blobs everywhere !
So bought some from RS Components and it worked great first time.

I have mixed experiences with Chinese vendors. Great pcb manufacture but some of the semiconductors blow up if you fart near them.