Unsettling message from LCSC about STM32 purchase... counterfeit? - Page 1
Forum section: electronics / general

author: foofus
author_rank: Newbie
timestamp: August 18, 2020, 07:00:42 pm
content: Hi, first post, glad to be here - and this is the only place I thought I could ask this question:I was ordering significant inventory from LCSC for our project and got this unsettling message from LCSC sales:---------------Thanks for your order #XXXXXXX-We got an update form our warehouse colleague：530 PCS C69216 in the order are separated 2 parts 511-19=530 PCS， the silk-screen on the item`s surface are slightly indistinct.Please confirm whether it`s acceptable.-----------So, these are STM32 processors; and I would never expect ST to ship parts that have bad silk-screening.What do you think? Do you think they're shipping B-stock with bad silkscreen, or counterfeit? Getting kind of creeped out. :-|I've ordered many parts from LCSC, and otherwise regard them as a reputable vendor.Thank you very much for your wisdom / help.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: August 18, 2020, 07:54:37 pm
content: 1. Determine if LCSC is an authorized distributor for ST.2. Are the parts with the issue the qty. 19 parts, the qty. 511 parts, or some other quantity?3. Are you able to get pictures of the "good" and "bad" parts?4. If LCSC is an authorized distributor for ST, then you would be able to bring this up with ST.5. If LSCS is an authorized distributor for ST, are you in their territory?6. If LCSC is not an authorized distributor for ST, they may or may not take interest.

author: thm_w
author_rank: Super Contributor
timestamp: August 18, 2020, 08:44:35 pm
content: https://lcsc.com/product-detail/ST-Microelectronics_STMicroelectronics-STM32F042K6T6_C69216.htmlI've not yet seen counterfeit STM32F042, and so far, no one has reported receiving any counterfeit ICs from LCSC.It could just be two batches of parts, if you receive them test a few from each batch.

author: ataradov
author_rank: Super Contributor
timestamp: August 18, 2020, 09:15:47 pm
content: They probably mean that date codes are different. This is normal if devices come from different batches.

author: Psi
author_rank: Super Contributor
timestamp: August 18, 2020, 09:36:05 pm
content: B-stock would be my guess, or C-stock or engineering samples

author: 3dgeo
author_rank: Frequent Contributor
timestamp: August 19, 2020, 10:12:45 pm
content: Well, keep in mind that LCSC uses their components in JLCPCB asembly service, so it might be that they just took those extra chips from the PNP machine. Different batch may look differently, even same Intel CPUs made in Malaysia looks different to ones made in Taiwan.I wouldn't go that far to say that they sell counterfeit parts. I actually bought their STM32F411 and same "counterfeit" parts from Ali – LCSC parts looks legit.You should have bought those chip and post the difference here.

author: Psi
author_rank: Super Contributor
timestamp: August 20, 2020, 12:59:43 pm
content: Quote from: 3dgeo on August 19, 2020, 10:12:45 pmI've had counterfeit parts form LCSC before. Not STM32's though.I got some fake 1A polyfuses that would melt the solder holding them on and still not trip.But a fake micro is on a whole 'nother level compared to a fake polyfuse.

author: Davlec Ltd
author_rank: Newbie
timestamp: August 20, 2020, 01:48:25 pm
content: Fake fuse or a misspick? I have a re-reeled strip of 300 " 0805 LEDs" from Farnell in our bonded area, absolutely not LEDs, probably are PTCs of unknown value.The weird thing about the OPs issue tho' is the fact they are even asking the question. Different batches of things can often come from completely different device packaging plants and have widely varying markings. Although I would say IME that is less true of ST parts (typically nice and legible) than it can be of some others.

author: foofus
author_rank: Newbie
timestamp: August 20, 2020, 04:28:08 pm
content: We got a message that seemed satisfactory. They said 19 of the chips had tape over the top, which was due to storage / packaging.I've never had a problem with parts from LCSC, but this was alarming at first. Thanks for the feedback.

author: Psi
author_rank: Super Contributor
timestamp: August 21, 2020, 12:35:32 pm
content: Quote from: Davlec Ltd on August 20, 2020, 01:48:25 pmDefinitely not a misspick, they looked the same as the polyfuses i ordered and the packaging was distinctive.They could have been a different trip current version, but they should still have tripped before melting the solder attaching them to PCB.