Showing results for 
Search instead for 
Did you mean: 

Discrepancy chip marking vs product/chip ID ? My chip marked STM32F100V8T6B give a productID 0x414, while I expected 0x420. Have I received a batch of chips with an incorrect marking?

Associate II

According to AN2606 rev 14, pid 0x414 mean high-density device, pid 0x420 mean medium-density device. We just bought 500 STM32F100V8T6B. They are deployed in an existing modular product that programs the uC in-situ. The program relies on the PID to correctly work (we use several different STM32F1xx's and STM32F2xx's).

Full marking on the chip:




KOR HP 642


Uwe Bonnes
Principal III

Did you get the chips from a respectable source? Ask your supplier!

Associate II

We got it from Kynix. Do they count as a respectable source?

Uwe Bonnes
Principal III

I never heard of them, findchips does not list them. Does some ST website reference to Kynix?

ST Employee

I do not believe we found Kynix from any ST website. See also my answer to Mike_ST.

Associate II

Hello Mike,

we bought these chips privately, so what happened here was that our purchase department independently sources these chips from Kynix.

So, I do not know if these chips are counterfeit, or wrongly marked, or downmarked. To determine if I can use them after all, it would be interesting to know what parts can possibly have a PID of 0x414. Is there a "reverse list", a companion to AN2606? I assume STM32F100xC STM32F100xD and STM32F100xE will have a PID of 0x414, are there other legal possibilities? Is there any way I could find out if any of these are downmarked (except if Kynix is indeed both honest and well-structured?)

Anything in the F1 line beside F105/7 with >= 256 kiB Flash will have 0x414 as MCUID


ST had been "downscaling" partially defective parts, especially with Flash errors.

I never heard of such a case crossing family boundaries.

I would suggest to approach an official distributor, or some ST representative.