How often do you see fake chips?

[thm_w]

The STM32F030 I bought from the same seller are counterfeit as well. The top is sanded down and re-laser marked. They also laser marked into the pin 1 marker which no one really does?
57 people buy a microcontroller and never test it   

https://www.aliexpress.com/item/32802747332.html

edit: seller had another listing for 100pc and there was one review claiming they tested it OK. So now I'm starting to doubt myself. But some of the ESD diodes are different readings, so I'm 99% sure there are differences in the chips..

[HHaase]

With linear regulators it's just rampant now. I can't remember the last time I've seen anything in a TO-323 package that wasn't counterfeit.  I used to use a lot of LM323's, 78H05's and as replacement parts in pinball machines.  Anything available now is usually the cheapest 5v regulator die available, stuffed into the big metal housings, with just some thermal glue holding it down inside the case.  Assuming it even works, you're lucky to get an amp of current, where the genuine parts are supposed to be 3A to 5A depending on the part number.  Any time you see blue insulators around the legs on something with that style package, run away and don't look back.

[wraper]

With linear regulators it's just rampant now. I can't remember the last time I've seen anything in a TO-323 package that wasn't counterfeit.  I used to use a lot of LM323's, 78H05's and as replacement parts in pinball machines.  Anything available now is usually the cheapest 5v regulator die available, stuffed into the big metal housings, with just some thermal glue holding it down inside the case.  Assuming it even works, you're lucky to get an amp of current, where the genuine parts are supposed to be 3A to 5A depending on the part number.  Any time you see blue insulators around the legs on something with that style package, run away and don't look back.

It is no surprise when buying no longer produced parts at shady places for low price. If there is no such part, they will 'produce' it for you. If you want genuine 78H05, look for NOS and be ready to pay $10/piece. Not $5/10 pieces. Also if you don't want to use modern parts in different package, thus using bodge wires, you can do this way https://www.ezsbc.com/index.php/featured-products-list-home-page/psu7.html#.XZia-kYzbuo/

[Yansi]

seen lots of fake 2n3055 tranys from ebay that short at 1 amp.

Well, 2n3055 tranny even in original state and form is so much shit these days it will not work in many applications.

Avoid using 2n3055 at all costs. There are way better cheap and reliable power NPNs these days.

[GerardG]

Got some fake lately.

Got some RGB leds that had anode at the opposite side.

Got some battery charging chips. I designed on microchip part that can have a 67k resistor on the Prog pin. The used part only works with maximum 20k on the prog pin.

This 20k was also mentioned in a datasheet for a pin compatible Chinese chip.
Assembly company showed the packing list for the components they bought.