Qualcomm has launched the 212 modem, a new chipset for NB2 bands that needs as little as 2.2 volts (V) to function. This may be advantageous for internet-of-things devices that need to keep going on ultra-low power in the long term. It is also small enough to allow for connectivity modules measuring 100 square millimeters or less.
https://www.notebookcheck.net/Qualcomm-s-latest-NB-IoT-chipset-needs-only-1-microamp-of-charge-in-sleep-mode.461910.0.html