SIL 2 micrcontroller requirement

[rajath]

Hi, 

We are working on railway projects where we are looking for SIL 2 microcontroller. 

As per our analysis we found out that we need to integrate the X-CUBE-STL package to make it to SIL 2compliance. And we have found out that it should have supported MCU's. As per our analysis the STM32H5 and STM32H7 series supports X-CUBE-STIL package. 

So, we wanted to know are the safety certified libraries available in this package to make it as SIL 2 compliance. Also, can you suggest if there are any SIL 2 certified microcontrollers available. 

Regards, 
Rajath

[Peter BENSCH]

Welcome @rajath, to the community!

Yes, certified libraries are included in the software package.

To access the software, however, you must first conclude an NDA (Non-Disclosure Agreement) via your local distributor or local office of STMicroelectronics.

Good luck!
/Peter

[rajath]

Hi @Peter BENSCH, 

Thank you for the quick response. May I know this software is free of cost or do we need to purchase the license to access this software?

Also, could you please confirm STM32H5 series supports X-CUBE-STL, or could you please suggest any other microcontroller which supports SIL 2 and have safety certified libraries.


Regards, 
Rajath 

[Peter BENSCH]

If you have agreed an NDA, the software package X-CUBE-STL can be used free of charge and without a licence.

STM32H5 of course also supports the STM32H5, details and further microcontroller families can be found in the X-CUBE-STL safety manuals (don't forget to open the complete list of documents by clicking 'Load More' several times or 'Expand all categories'.

[Ozone]

Dealing with projects requiring SIL-2, I suggest a Cortex R device. Preferably a dual-core lockstep configuration.

And from experience, I would highly recommend to consider an off-the-shelf ECU fulfilling this requirements.

[Pavel A.]

ST already has some Cortex-R products? https://www.eenewseurope.com/en/st-plans-integrated-automotive-microcontroller-line/

 

[Ozone]

One that note, not recommending one vendor or another ...

There are significant follow-up choices to make regarding a controller for a SIL-2 project.

One is the choice of a realtime OS - excluding an attempted bare-metal implementation (most likely to become a development and/or maintainance nightmare).
While there are free options (like FreeRTOS), they will imply higher costs downstream, because basically the whole project software must pass the certification.
Some pre-certified professional options (e.g. SafeRTOS) avoid a lot of this hassle, but come at relatively high initial costs.

And lastly, all those certifications (of either option) are bound to a toolchain. A replacement of this toolchain or even a major update will require a renewed certification process. With commercial safe RTOS variants one is usually bound to the vendor's choice, as RTOS and toolchain are pre-certified in tandem.

[LCE]

I have worked for a company with SIL products - my job was luckily in a "pre-development" department where we could simply play with and test new controllers / sensors.

But the product development department had as many SIL-experts as development engineers, alone the testing regimen...

So, judging by your questions I would advise to find some experts - it's much more than choosing the right controller and SW package.

[Ozone]

> So, judging by your questions I would advise to find some experts - it's much more than choosing the right controller and SW package.

I would definitely second that, dealing with software for SIL-2 systems as well.