Small LoRaWAN nodes

These are not certified, the RFM95-98 LoRa modules don’t have integrated LoRaWAN functionality (like the RN2483 from Microchip). Therefore they can’t be LoRa-Alliance certified.

throw in 14.2 by 22.3 mm here, double the size but still pretty small.

Hi, l have made a 23x38mm node, feedbacks are welcome in this topic :grinning:

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Thomas, this looks pretty neat and compact.

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Sometimes it can go quickly :grinning:
Great news all these news developments. I see the announcement of two new nodes this week.
Keep up the good work!

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very similar to the Moteino MEGA, but with a far better SMA antenna connection.
@eTh0maz : for LiPo batteries usage: is there a protection against deep discharging?

that is normally build-in the lipo

That could be true for the lipos that you know but please don’t bet your lipos on it.
This little friend here will happily keep draining, I have a swollen one somewhere to proof it.

Sorry to hear that, please get well soon. Here is a pint of Guiness to get you back on your feet. :slight_smile:

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I have some experience with LiPo’s and charging and if you buy a LiPo, be sure that it has PCM (Protect Circuit Module) inside.
My favorite ’ LiPo shop and ‘trusted’ source.

To charge them I use normally these little 'modules

another possibility to feed a low power thingy are rechargeable coin cells eg LIR 2450 - 3.6v 120 mA
(carefull, they are a litlle bit bigger than the 2032 in your PC)

together with the special size 'button cell pcb holder they work great for low power electronics.
to charge them outside your circuit use something like this
or you can use a ‘tweaked’ eBay charge module (replace a resistor)

(thank you Terrence :smile: )

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That explains the difference then. I use special lipo chargers and before this I only used LiPos on systems with low voltage warnings, that’s why I never bought one of those.
Thanks for the link! It may just come in handy later.

My first prototype, with Atmega328p, was inspired from Moteino. After all, i’ve changed the complete design I started with. The only feature left is that’s about the same size :smile:
There’s no charging or protection circuit. I’m planning to add this in the next version, if you know some good and compact circuits you can always suggest these.

@BoRRoZ
About lipo, did you noticed any problem using them outside at low temp? Felix from lowpowerlabs told me some months ago he had problem with them at temperature below 0°C, they simply shut down.

@eTh0maz
Excellent design, would you share your Antenna SMA-UFL library (if it’s done with eaglecad)? I can do it, but your is perfect, and sharing will bring me some more time to do other interesting stuff :wink:

By the way I made a RN2483 shield for WeMos ESP8266, works great so far.


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Hi Charles,

No, I didn’t know that, I’ve made several projects that are powered with lipo’s and placed in the open, but they are build inside waterproof project boxes and I always ‘tape’ the lipo’s, never had complaints, maybe lucky. :sunglasses:

But good to know, I’ll have to investigate this , will put a fully charged LiPo in my freezer !

nice pcb !

@BoRRoZ
Thanks, Oh, good idea, will be nice to know your tests results with lipo in the freezer :wink:

About the LiPo temperature: This is true. Cold LiPos perform terribly. When we are in situations where we need a lot of power from a LiPo, for instance when flying a drone, LiPo temperatures below 14 DegC are a big no. We then use special heater boxes or store them in a warm car or other warm place before use.
I suppose for low power requirements like nodes the tolerances are a lot bigger but I would not be surprised if you see an effect.

That (nice) circuit board says “Lora Gateway”. Does that imply you used an RN4283 as a single channel gateway? Some would love that. Or should it actually say “LoRaWAN Node”?

@arjanvanb
Well, sorry about that, in fact I designed some gateways for other projects with other modules mainly RFM12/69 and done this one for testing before I learnt that RN2483 as a gateway is very complicated :grin:

Yeah, it’s more a LoraWan node :wink: but may be it’s possible to do a gateway with this other design which use classic hopef RF95/96/98 module footprint. I’m pretty new on LoraWan, so sorry about my noob design.

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Looks interesting but seems to use way to much power (80mA?).
I could not find any hint how to put it into low power modes in the NavSpark forums.

TvB Board with RFM95W (fixed connections), running LMIC1.5, BMP280 (druck & temp); HTU21D (temp & humidity); 1000mA LiPo, deep sleep for 5 min LowPower).
Looking forward how long the battery holds…

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