Any STM32WLx-based modules with RoHS and CE?

Hi all

The LoRa module I used to use (Murata CMWX1ZZABZ) has been out of stock globally for months and none expected till Q2 2022 if I’m lucky.

I’d like to use ST’s new STM32WLx chips, but they don’t provide CE-certified modules, which I need.

I’ve found Seeed’s LoRa-E5 module and development boards but none of them are RoHS compliant (it’s a bit naughty they mark their modules with a CE mark despite this, see here) and as a result I can’t really use them for what I need in the UK (plus I’m just not a fan of lead).

Does anyone know of any CE-marked, RoHS modules? Preferably with dev boards too? STM32LWx preferred but will probably take anything with a reliable stock!


How can you tell?

The documentation includes both CE & FCC certificates …

Classing Seeed as ‘a bit naughty’ for allegedly inappropriately marking their products CE could end up distracting you from your original goal &/or end with you in gaol - you make it all to easy for them as London is the world’s go to destination for libel cases. Out of their approximately 300 staff, I’m sure one is a lawyer.

As Farnell have the STM32WL55 on delivery dates from 7/11/22 to 4/1/23, I can’t even offer to make some for you.

I’m using the Microchip WLR089U modules which is both ROHS and CE and UK and USA and a few other places certified. Next batch due late January. New orders shipping for mid-June '22 on their main site.

Is your project for retail or domestic use? That’s where CE becomes critical.

I always thought it was the final assembled product that needed to follow CE …

It is, but if you build stuff that’s all CE, you can simplify the certification or even self-certify.

I hope this won’t become a classic internet “who’s opinion is right” fest. That wasn’t what I hoped this forum would be about. Taking time off work to defend my writing then, here we go:

RoHS compliance is not mentioned in any manufacturer documentation or product web pages. It’s normally something companies like to make clear if it’s there. Another good tip for finding out is to check-out the relevant listing reputable electronics distributors, i.e:

Arrow (maked as RoHS not compliant)
Mouser (RoHS information would be shown under product category in spec table, see other items. Also not listed if tick RoHS in search)
DigiKey (empty entry in RoHS)

Several weeks ago during my initial searches I e-mailed Seeed directly asking for their RoHS status. I was sent these radio and EMC sections of their CE-related tests back too. They did not respond to my question whether RoHS was needed for their CE mark, despite my direct question.

Yes, their certification shows they are CE-compliant in some categories, but those provided do not cover all elements.

My end-goal is to design (and indeed use) a legal product. Hobbyists would perhaps be less inclined to be “distracted” by such paperwork, but I am not doing this for myself.

I think it will be a worrying time when people are too scared to use the words “a bit naughty” about a company if they have legitimate concerns (you did read the justification link, and others like it?).

Thankfully, not everyone has reached that point yet.

If Seeed want to give a great PR boost, feel free to use this post as a springboard to dispel my concern and anyone else in the community :+1:

Thank you for the well-meant offer. I suspect you would not be as generous to put the module you create through CE testing at a certified testing house, particularly regarding the radio/RED aspects. The costs in time and money my company has spent on this over the decades on our own custom electronics doing so is why CE-certified modules are rather popular in industry.

Thanks, this is more like it(!)
I’d previously dismissed the WLR089U a while back but looking over the spec again I’m not entirely sure why, since as you say its CE and RoHS checks-out. Perhaps it was supply issues back then too, since now it’s no better than the original Murata module. I wish we’d stockpiled at first sign of issues.

As you’d have guessed by now, retail.


Taking time off work to answer …

As is evidenced across the forum, with many different Far Eastern suppliers their communications can be very variable both online & emails. Whilst frustrating that they haven’t responded (have you tried the forum, their contact form or phoning them up) I’d assume on the side of them not using leaded solder given that they are aiming to sell world wide at all levels. Travel hopeful.

Even UK manufacturers like RF Solutions aren’t a model of clarity:

RF-LORA module is CE Compliant and meets the requirements for FCC part 15.

Does that mean it has been tested - I’d infer not. But wait …

RF-LoRa2 module is identical to RF-LoRa with the addition of an integrated ufl connector and screening can. RF-LORA2 was developed with the aim to achieve FCC certification of the module.
This enables the end product that RF–LoRa2 is incorporated into to automatically use the RF-LORA2 module FCC certificate without further testing RF-LoRa2 module is available 915MHz.

So they stick a metal can on the top and now it appears to have FCC certification.

But no certificates on the site …

As for the distributors, as their data quality is poor on a good day, something I can substantiate with multiple examples from using parametric search options with multiple entries for basically the same thing - switches being a wonderful example but RS, for instance, can’t make up their mind about how many different versions of Atmel family names they think exists.

So, not naughty at all to put CE on their product.

I’m allergic to random diss’ing of vendors, they all have their foibles, expressing concerns that they haven’t published ROHS info or responded to your emails is one thing, implying that the CE mark on their device is not legitimate is rather different.

I am aware of the ROHS regs, being a manufacturer of microcontroller based boards. I tend not to use other manufacturer’s websites as a source of legal knowledge but sure, if you want CE marking for your commercial products, then it needs to be ROHS.

So perhaps as Seeed have a CE certificate for the product, the testing house has covered ROHS but you haven’t yet found this out. Just because you don’t know, doesn’t mean they aren’t.

As for opinions, everyone has them, like bum holes but everyone’s opinion is correct, that’s the point of an opinion as opposed to a fact. My opinion is that it’s not fair to say something about a manufacturer unless you have facts, not supposition.

On to more productive aspects:

The WLR089U Xplained board is around for prototyping but UK distributors only have the SAMR34 version (pretty much the same for getting started).

There are WLR’s in the supply chain in random bursts, so ordering now should yield some by the next anticipated January drop. Depends on how many you need & how quickly.

An alternative is to look at the radio modules - like the RFM95 which has ROHS docs but I’ve not looked for their CE compliance for RED. From that you can add an STM32L of some sort and build your own Murata module and use the CubeMX LRWAN1 as a starter (to going mad, but some reorganising of the code base can make it less cumbersome to navigate). Or see if RF Solutions can pony up some docs to give you a starter.

I said they replied to my e-mail(s). I don’t think telling me to use a contact form or forum was a great use of your work time, nor your anecdotes about how “Far Eastern suppliers” behave or RF Solutions issues.

Distributors databases aren’t perfect but given their regulatory responsibilities as major importers they’re generally pretty good. When three independent distributers say the E5 module is not RoHS compliant and no mention of RoHS is made in the original company website or documentation, honestly, why are you digging your heals in here?

That’s very disingenuous to cut-off the rest of my sentence in your quote, when the full line was:

The link I provided to justify my concern clearly states “All non-RoHS products cannot have the CE Marking”. I am not just “randomly diss’ing vendors” and don’t know why you having such an issue with me pointing this out.

If you want to give Seeed all your love you crack on, but my company requires base evidence for compliance, which is found quickly and easily for most reputable products.

Due diligence is not about giving the benefit of the doubt. I don’t understand why you’re so passionate about doing so, nor why you are so clearly very angry with my posts.

If the manufacturer or importer puts a CE-mark on a device, this means that this device fullfills all relevant requirements of all relevant European Directives. This device can be put on the market.
But who is responsible, that the requirements are fullfilled? If the manufacturer who puts the CE-sign on the device is within the EU, he is responsible. But if you import a device from outside of the European Market and put it on the market, you are responsible that all relevant requirements are fullfilled. This is independent of a CE-mark issued by the (e.g. Asian) manufacturer.
You have to issue the Declaration of Conformity and put the CE-mark on your (new) device.
As already said, the CE-mark can be based on a self-declaration. In most cases there is no need to involve a (independent and competent=accredited) test-lab.
But the only thing you should rely on is a test-report of an accredited test-laboratory.
One of the worst examples are power-supplies that neither fullfill the requirements of the LVD (electrical safety) nor of the EMC-directive. If you import these power-supplies from Asia and sell them (as part of your device) in the EU you have the full responsibility for all accidents that may happen because of devices not fullfilling the requirements for electrical safety.

One rabbit hole with CE, is the assumption that there is an exemption for personnel or DIY stuff since the RED guide states that CE is required for all stuff ‘put on the market’ but that there is this exemption for personal stuff.

However when you cross check the more complete Blue guide, you will find that CE is required for all stuff ‘put into service’ and there is no personnel use exemption.


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Hello Matt,

this module should have all required certificates.
STM32WL with CE and RoHS (dnt-TRX-ST1)

Thanks for the suggestion.
No mention of RoHS for the module nor the development board though.
I’d be a little concerned about the expected supply/support life of this one too.


There are RAK LoRa nodes with CE, FCC, RoHS, etc, certificates :

For example RAK4631, RAK4270 and RAK811.

Yeah, there are some LoRa nodes without RoHS, like RAK4600, RAK3172 (STM32WLE5), etc.

We had been using the ABZ module and had to make a switch to Murata’s 1SJ module (at the last minute due to availability issues. It was a redesign effort but not too bad. Murata provides patches so that ABZ based ST’s SDK can be upgraded to support this module (but only for specific versions of the SDK).

Hope this helps

Thanks for suggesting these modules; I’d not heard of them before.
Their certification is well presented and it’s great to see a company who cares about such things!

Since they’re based on Nordic chipsets and come with their own base boards it would require a major redesign of both our hardware and software to accommodate them in the current project. Still, I’ve bookmarked them for potential future use.

Thanks again!


Only one of them - RAK are MCU tarts - do one of everything - including the RP2040 now!

The RAK4600 is a nRF52832 module, the RAK4260 is Microchip SAMR34, the RAK4270 is STM32L071 + SX1262 and the RAK3172 is STM32WL55.

All of them available as SiP like this:


And for the record, because Google indexes and presents results from this forum as a priority so it’s only fair to be accurate, because we all know what a short temper I have :wink:, the dnt-TRX-ST1 is fully CE compliant with RoHS. Not sure why they’d go EoL in short order, but with the current supply chain issues I’ve reworked most of our base boards so that I can swap out the radio - costs a bit more on PCB real-estate but saves so much time on sourcing.

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Ah yes, my apologies (I just checked-out the first one mentioned, the RAK4631) - I hadn’t appreciated the vast range to choose from!

The RAK4270 looks promising. It’s a shame the RAK3172 (based on the STM32WLE5CC) doesn’t have a tick on the RoHS but the RK4270 would at least be the same as our present setup.

I’d expect so given they’re a German company (I think) but as with all these things my concern is I couldn’t find that written anywhere (and as they don’t seem to be available through standard distributers couldn’t check there). Can you provide a link to their RoHS confirmation?

This would be great and nowadays seems a sensible idea. The problem is we currently use the CMWX1ZZABZ to perform many other actions other than just acting as a modem (it reads the GPS and IMU sensors and communicates with the main processor with a custom protocol). We could add another intermediate microcontroller to do this and literally just use the lora module as a modem, but it’ll be a significant waste of space and resource given it all works on the single module at the moment. I guess compromise is needed.

Wow, they’ve sneaked that one in since I was last on their website checking out the ABZ. The 1SJ seems like an almost perfect replacement (minimal changes). The upgraded SX1262 is good.

Stock seems to be OK at the moment for small quantities. I’ve ordered a bunch of eval kits.

I can’t believe I missed this one, thanks very much!


Given all the stuff RAK make & sell in the EU, I’d be very surprised if they’d gone with lead based soldering for just that one product. Much much more likely they’d forgotten to put the info up on the website. You could email them to check in on it.

The RAK4270 is somewhat output pin constrained, no where near the same as the ABZ but OK for a simple I2C or just acting as an AT modem application.

Sorry no, but you can ask them for the docs …

It was to backup your statement you were keen to make that they were fully compliant with RoHS. I’m not asking you do to my work.