You will need to replace these with similar components tuned to 915MHz.
The 915Mhz path is what is connected to port J1, so i was’tn planning on taking it out… The 868 port is whats on the side i marked off to remove. The RF switch chooses which side…
That’s interesting. I have a Dev Kit but not had the time to get it working. Learnt something very interesting. Thanks
Have a read of Microchip AN2842 page 12 which talks about the matching networks for 868 and 915… RF is blackmagic to me. I am a bit lost.
for regions with +14dBm max output power (868…), the PA_BOOST path is not needed.
for regions with +20dBm max output power (915…), the RFO path is not needed (but it is recommended because it is very efficient in low power transmissions).
in both cases you can save some bom cost removing pasives and changing SP3T to SPDT.
For a multi region design you need the 3 paths
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I’m confused here… I thought The choice of path is is between a filter set for 868 and 915, not between if its using the PA, RFO.
the pasives values are almost the same for 868 and 915.
but yes, you can tune RFO pasives for 868 and PABOOST values for 915.
Hey guys.
I added all the project files to my Github (TinyLoRa). Please feel free to check it out. I’d really appreciate any feedback you guys can give on bugs and future improvements.
Cheers,
Orkhan.
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Which board are you using ? Is it armmbed compatible ?
Do you have any code yet?
To do some basic testing I simply used the example codes from Atmel Studio (ASF v3.45).
Once you move past the basic examples ( which work quite well ) unorutanty things get pretty rough pretty quickly… The ASF wizard for the R34 is very incomplete. For example i’m just doing some work with generating some PWM. Its just not there. The workaround is to use some L21 code, but then you have to give up on ASF…
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I’ve project code for LoRaMac-node and SAMR34 with Keil. But need found it from previous year. I’ll add to my github if found. If TinyLora owner can connect it via debugger to computer - i can debug over internet.
What type of plans / use cases do you have for this platform ? Your choice of feather form factor is a great selection.
One item you might consider is to allow controlling the power to the RF switch in the design.
today you have it directly connected to VDDA ( like the Microchip eval board ) but this RF switch will draw between 5 and 7 microamps by itself when the SAMR34 is in any of the deep sleep modes, so it is the controlling factor for ultra low power vs the modes of the SAMR34.
Since your breakout/feather board will also add extra currents, maybe this is not a problem for you. Just be aware of this added current. Maybe the power to this device could be carefully controlled by an IO pin.
Depending upon your region, a shield might be required over the module circuitry if it was to go thru regulatory certifications.
Will these be available assembled or semi assembled somewhere ( BGA is hard to handle)
K
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Greeting from Australia Okhan, I just ordered one. 
Did you use the Microchip RF reference design which can do both 868MHz and 900MHz?
Have you been able to test the receiver sensitivity to see if there are any anomalies
Regs Joey
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Hi, Joey
sorry for the late reply. I just saw your comment.
Yes, I mostly used the Microchip reference design, and it supports both ranges.
Since I don’t have proper RF testing tools, I could only rely on the reference design. So far it seems to work without any issues.
Regards,
Orkhan
Hi All,
Anybody know Lora alliance certification process for SAMR34 Device. As per my understanding we need to do certification for loraWAN stack. Please correct me if I am wrong here. What will be the Lora Alliance certification process for SAMR34 module (custom module)?
A module by itself can not be certified. Only a complete node : module, LoRaWAN stack, application code and antenna can be certified.
Look at the LoRa Alliance site for information regarding certification. You might find this video of a talk on the certification process interresting.
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