The Electron is not recommended for new designs, so that’s out. That leaves three possibilities:
- E Series E310 (Global 2G/3G) and E402 (US LTE Cat M1), Gen 2
- Boron 2G/3G (Global 2G/3G) and Boron LTE (US LTE Cat M1), Gen 3
- B Series SoM B523 (EMEAA LTE Cat 1) and B402 (US LTE Cat M1), Gen 3
They’re all different form factors:
- E Series: SMD module, soldered to your base board. Older Gen 2 design.
- Boron: Intended for prototyping, has male header pins on bottom for socket mounting or could be wave soldered.
- B Series SoM: Module fits in an M.2 NGFF socket. Held in place with a screw.
While the B523 is not officially supported in Australia yet, it most likely will work, and will be officially supported in the next several months. The main advantage of the B523 is that it’s LTE Cat 1, with 2G/3G fallback, so it will continue to work in places where 2G or 3G have been phased out.
Since the phase-out of 2G/3G is coming soon to the United States, all of the devices recommended above are LTE Cat M1 so they will continue to work after 2G/3G sunset. Since there isn’t global LTE Cat M1 roaming, you’ll need to have at least two SKUs for support of both US and EMEAA.
The Boron is handy because it has the fuel gauge and PMIC for battery powered applications on the module. However, it’s physically impossible to fit the LTE Cat 1 modem module (Quectel EG91-E) in the Boron form-factor. So the B Series is more future-proof that way.