Wanted to share a new variant I have been working on for the last several weeks. It pairs the Xiao nRF52840 with an Ebyte E22-900M30S. For me this was sort of a holy grail as it combines the Ebyte’s 30 dBm Tx power with an idle power draw that’s not terribly far off from that of a RAK 4631, and is also pretty compact.
Looks like my PR was just merged (thanks @thebentern!) so the variant can be found here. Included there is a short how-to doc (README.md) which details the steps needed to get it running. I also drafted up a basic PCB for this setup which is here. It’s pretty easy to wire up on a protoboard too; the pics below are of an early build on an Adafruit “small tin” perma-proto, which is a near-perfect size.
Yes indeed. I have a first attempt that integrates the MiniBoost and JST/switch circuits into the schematic (instead of using the breakouts) but even better would be to include a solar charge controller of some kind – maybe even your LTO setup? Though I know that’s still a work in progress. In any case, I’d be psyched to collaborate on something to that effect!
I’ll reach out on Discord. 3 of us are actively working on something like this. If we use the CN3791 battery IC it could handle charging from USB and from solar (li-ion only). The TPS61023 IC looks like a good choice to integrate on the board.
I’ll give one of these boards a try, thank you. I have some IP2312 units coming, which are also rated to run at 2A, but I just ordered a couple C3791 based boards to try as well. TY. CN3791 Datasheet
Looking at Figure 1, it would be nice if any manufacturer placed a jumper or switch between R1 and D3/D4 - the ability to turn off the indicator lights, without using a soldering iron, is a must-have.
