Hey guys!

I just released a new version (revision v5) which will be the version I am going to produce from now on. This version adds LiPo support and I will explain why:

In the beginning with v1 I actually already had LiPo battery support because I played it safe, but then I found that the SIM7000A worked flawlessly without the LiPo battery so I removed it in subsequent versions. This is because the SIM7000A only supports LTE CAT-M1 and NB-IoT and therefore draws a fraction of GSM power consumption. However, with the SIM7000C and E versions they support fallback to 2G and 2.5G so power supply becomes an issue and the module will enter a reboot cycle in GSM mode. However, if CAT-M1 or NB-IoT is available, use of the battery can be avoided by setting the module to only use those two modes and not GSM. Again, for SIM7000A users this is not an issue at all and you can simply leave out the LiPo battery and it should work just fine!

Revision v5 adds a JST connector for standard single-cell LiPo batteries like those found at Sparkfun and Adafruit and also includes circuitry to charge the battery at 500mA. Because of this charge rate the battery should be at least 500mAH capacity (1AH or more is ideal) to prevent damage. Also, higher capacity batteries will be able to supply more current to the module for large spikes. Moreover, now that a battery can be connected to the shield, the "b" command in the LTE_Demo can run and monitor the battery voltage and percentage!

In this revision I have also attached the normally disconnected pin on the Arduino to VBAT, the LiPo battery voltage (also equivalent to the SIM7000 module's supply voltage) for convenience and debugging.

Another reason I decided to add the LiPo support is because the firmware updater tool only works if the module is powered by a robust power supply (such as a LiPo battery). You can find the firmware updater tool files here on Github.

As always, you can view the latest design files and full schematic on my Github page.

As a quick reminder, my Indiegogo campaign for this shield launches midnight tonight (Eastern time) so be sure to check it out!

Thanks,

Tim