Hi,
I am connecting a sim7070 breakout named SIM7070X-EVB that runs NB-IOT. I used some time to find a way to run it with an Arduino MKR Zero. It is a bit different from other breakouts like SIM7020 and SIM7080 So I am documenting it here.
How to power module with 3V logic:
Connect 5v to Power will power on module in standby 7ma.
Connect 3.3V to V_MCU to have 3.3V signals.
Connect pin to PWRKEY and powercycle: run High Low High.
Ekstra AT-command will activate modem.
Turn off modem with a new powercycle/at+cpowd=1.
Will turn modem into PSM-mode 0.1ma.
Turn modem completly off with pinmode HIGH on PWR_EN
and on with LOW.