Thank you for publishing this. Adding a battery is not possible everywhere due to the limited temperature range and increased regulatory requirements.
You are stating for the power supply of the B402:
The recommended input voltage range on this pin is between 3.6V to 4.2V DC. Make sure that the supply can handle currents of at least 2 A.
A supercapacitor being able to supply 2 A for 30s with a voltage drop of 0.6V would have a capacity of about 100F, which is quite big. The modem will probably not need 2A in this 30s, but how much energy does it need?
- Can you please specify the requirements (max. current, energy) of the backup power source?
- What about the Quectel modem on the B524? Can you confirm that this modem is not affected by this issue?