About Matter and Thread Certification

[gceti.1]

Hi,

I hope everyone is fine.

I have question about Inheritance Certification.

The Thread Group says;

The Thread Group allows certification by inheritance for families of end products that reuse the same Thread system (chip and stack) and the same use cases.

When appropriate stack libraries and SOC or module used End Device Certification can certifiable by Inheritance.

Our company does not have any Thread or Matter-certified products, but if we use ST's certified module and stack library, can we obtain Thread certification for an end device we develop?

Can we use the certification by inheritance feature when using ST's modules?

We want to use a Matter-enabled module and a certified stack binary in our projects; however, we will design a PCB using this module.

We would like to confirm whether soldering components onto the PCB with the module or chip would invalidate the certification by inheritance.

We would greatly appreciate your support with your experience and knowledge.

[EPASZ.1]

Hello,

yes, you can get the Thread certification by inheritance. But for Matter certification itself, the process is different - there is an option similar to inheritance, but it is related to each individual device type (so light, switch...) and possible cluster configuration. ST does not have such certification at the moment, so it is up to the customer (apart from the applications which are publicly available in the X-CUBE-MATTER package). We can help with pre-certification tests (making sure the device pass cluster functional tests) but the customer needs to apply for membership in CSA and officially pass the tests.

[gceti.1]

Hi,

Thank you for reply.

I have little bit knowledge about Matter certification processes. But, before Matter certification the device's network layer must be certify. At this situation we want to use both Thread and Bluetooth. I just wonder what if we use ST's matter certified module and SDK, Must we still test the device.

[EPASZ.1]

Hello,

yes, that's what I was trying to say. Maybe it is not clear.

You need to use the M0 stack binary (otherwise, the WB5M cannot operate in general) - this binary manages the network layer. And it is certified as such. It has BLE 5.2 certification and Thread MTD certification. You do not need to do testing of the device.

But you need to provide your own BLE and Thread certifications when you want to apply for Matter certification. You can use ST BLE certification as described here https://wiki.st.com/stm32mcu/wiki/Connectivity:Certification_guideline#Qualification_workspace_process_flow . And you can apply for Inheritance certification for the Thread part. This will be the input to step 6 of the diagram you linked above.

And if you are asking about the product testing in step 5, then this concerns the Matter application layer, which you need to do.

[gceti.1]

Hello,

Thank you for your response.

I apologize for asking repeatedly, but I want to make sure everything is clear.

When we solder an ST Thread and BLE certified module onto any PCB and design a final product using this module, we can directly skip the Thread and BLE Certification steps in step 4. Since this ST Matter module is already certified, it should suffice to present its documentation to CSA, correct? I am asking because our hardware team has indicated that network transport tests might need to be redone when a new final product is developed using the module. Therefore, clarifying this point is crucial for us.

For step 5, we need to have the Product Testing conducted at a Matter-accredited test laboratory.

In conclusion, since designing a new PCB using a certified module does not invalidate the Thread and BLE certifications, we can proceed directly to step 6. In this step, we can declare the previously obtained certifications, correct?

Even when using certified products, is it necessary for the company to register with the Thread and BLE organizations?

[EPASZ.1]

Hello,

"Even when using certified products, is it necessary for the company to register with the Thread and BLE organizations?" - The simplified view is that ST has certified its product as a component. You then need to register with the given organizations in order to certify it as part of your end-product. You will not be required to do most of the "physical layer" testing (because you cannot change the module's HW) and none of the BLE profiles or Thread functionality (because you cannot change stack SW). But your end-product still needs to be registered and certified by itself.

For BLE, you can skip PHY testing and you can provide the QDID from ST. But you need to do Regional certification testing (section 3.2 in the article I linked above) - this is non avoidable. Maybe this is what your colleagues had in mind?

For Thread, you can directly do certification by inheritance.

"we can directly skip the Thread and BLE Certification steps in step 4". Not really. It should be a much simpler process than a full certification, but you cannot skip.

"Since this ST Matter module is already certified, it should suffice to present its documentation to CSA, correct?" & "proceed directly to step 6. In this step, we can declare the previously obtained certifications, correct?" CSA will ask for your own certifications, cannot reuse the ones from ST.

[gceti.1]

Hi,

Thank you for your clear reply.