Counterfeit F103s

Anything not related to STM32
Fitch
Posts: 5
Joined: Mon Sep 04, 2017 3:26 pm

Counterfeit F103s

Post by Fitch » Mon Sep 04, 2017 3:59 pm

Hello,
Does anyone have any data on counterfeit F103s?

I have a blue pill that reports 128K, which is cool since it is marked F103C8. However, I have an STLINK V2 clone that is marked F103C8 and its flash size register contains 0xFFFF. I also bought some Maple Minis from Ebay (china) and even though they are marked F103CB, they report only 64K flash.

Is there a way to tell if chips we have are real or not? I ordered some F103CBs from Ebay, but now I suspect they will be fake as well. They were $1.90 each and the single piece price at Digikey is more like $6.43.

Thanks!

User avatar
Rick Kimball
Posts: 1056
Joined: Tue Apr 28, 2015 1:26 am
Location: Eastern NC, US
Contact:

Re: Counterfeit F103s

Post by Rick Kimball » Mon Sep 04, 2017 5:35 pm

I would think if you really cared you would buy from an authorized distrubutor. The other alternative is to use the low cost Nucelo / Discovery boards. They would still be low cost (assuming you are in the US) but they will be made with real chips for sure.

If you go the China route, you pays your money and you takes your chances.
-rick

dannyf
Posts: 167
Joined: Wed May 11, 2016 4:29 pm

Re: Counterfeit F103s

Post by dannyf » Mon Sep 04, 2017 7:04 pm

Is there a way to tell if chips we have are real or not?
short of asking ST, nothing definitive.

Aside from GD32 chips, those "counterfeits" are likely mis-marked (purposefully maybe?) other STM chips. it could be a STM32FEBK, for example, a lower capacity STM32, a refurbished STM32, or a repackaged STM32 (from die), ...

chances of someone other than ST making a brand new STM32 are low.

Fitch
Posts: 5
Joined: Mon Sep 04, 2017 3:26 pm

Re: Counterfeit F103s

Post by Fitch » Mon Sep 04, 2017 7:34 pm

I have known about fake Atmel chips, but they are quite a bit simpler than the F103. I would not have expected to see so many. I bought several blue pills and some Maple Minis and an STlink clone, all from different sources and they all appear to have fake chips on them. So I am batting 1000.

Guess I will break down and buy a couple from Digi-Key.

Thanks all.

User avatar
martinayotte
Posts: 1229
Joined: Mon Apr 27, 2015 1:45 pm

Re: Counterfeit F103s

Post by martinayotte » Mon Sep 04, 2017 8:59 pm

Having chips reporting 128K doesn't means they are clone. In this forums, many of us discovered that a while ago.
We suspect that ST is using the same die for CB and C8, but, during testing, they mark it C8 if some of the flash cells on the second 64K reports some errors.

When you will get some F103C8 from DigiKey, please report back here what is the flash size is reporting.

User avatar
RogerClark
Posts: 7438
Joined: Mon Apr 27, 2015 10:36 am
Location: Melbourne, Australia
Contact:

Re: Counterfeit F103s

Post by RogerClark » Mon Sep 04, 2017 9:48 pm

There is at least one other thread which discusses this topic

it should be merged, with one of those.

Edit.

See

viewtopic.php?f=39&t=2500&hilit=fake

http://www.stm32duino.com/viewtopic.php?t=110

viewtopic.php?t=1323&start=20

dannyf
Posts: 167
Joined: Wed May 11, 2016 4:29 pm

Re: Counterfeit F103s

Post by dannyf » Tue Sep 05, 2017 12:16 am

So I am batting 1000.
maybe you should think about buying lottery ticks now.

seriously, we all could use some of your wisdom in identifying fake chips if you don't mind sharing.

dannyf
Posts: 167
Joined: Wed May 11, 2016 4:29 pm

Re: Counterfeit F103s

Post by dannyf » Tue Sep 05, 2017 12:20 am

the observation of more ram / eeprom than specified in the datasheet on some stm parts has been around for a long time. I tried that on STM32F030 and then STM8 back in 2014.

the same can be said about usb capabilities as well - you may see some non-USB capable (per datasheet) STM8s used in USB applications natively.

or UID on parts not specified for UID....

obviously, the risk of relying on such things is entirely on you.

Fitch
Posts: 5
Joined: Mon Sep 04, 2017 3:26 pm

Re: Counterfeit F103s

Post by Fitch » Tue Sep 05, 2017 12:41 am

Guys,
I understand that a chip sold as 64K that reports 128K is not by itself indication of a fake. My issue were parts clearly marked STM32F103CBT6 that read only 64K. Note, I just read the flash size register I did not try to test the flash for size.

But thinking about it, I am sure the flash size register is programmable by ST, and I would suspect even if they use the same die that they would program it to be the size of the part they mark rather than program it larger. So maybe reading the wrong flash size either more or less is indication of a counterfeit? Just thinking out loud.

User avatar
RogerClark
Posts: 7438
Joined: Mon Apr 27, 2015 10:36 am
Location: Melbourne, Australia
Contact:

Re: Counterfeit F103s

Post by RogerClark » Tue Sep 05, 2017 12:56 am

I asked ST privately about whether they had heard of fake chips and they did not know of any.

They know that the GD32 are a "clone" but are actually completely different MCU's, which were designed to be functionally equivalent but not a direct copy, but that is a lot different from fake chips

(Note. The GD32 are not actually functionally equivalent and have a number of small differences which means STM32 binaries don't always run on GD32 chips)

Post Reply