I’m working on a project were I need to power to some 24V 4-20mA sensors, a 3.3V ESP32 and a 5V SIM808 module.
To accomplish this I’m using a step-down buck converter to reduce a 12V electrolytic battery to 5V and with an LM1117-3.3 feed the ESP32, then I use a step-up buck converter to feed the 4-20mA sensor.
My issue is feeding the 5V SIM808. I tried hooking it up just in the input of the LM1117 but the issue is that when the battery discharges a bit the 5V drops and the module turns off. I thought on adding a LM1117-5.0 that allows an input from 5-12V but since this is battery powered I wanted to see if there is a more energy efficient way.
Any help would be appreciated. Thanks!