I am using 3.7V LiPo battery and ESP-12E in this project. I need to monitor how much charge is there in the battery to help when battery falls below certain level and notify to charge it up again. I've red that 3.7 LiPo batteries maximum voltage goes upto 4.2V. And readable analog input voltage for ESP-12E is 0-1V. I was planning to make a simple voltage divider to convert 4.2V to 1V and provide it to analog input of ESP-12E. Voltage divider resistors - Input Voltage:4.2V Output Voltage:1V R1: 1 Kohm R2: 330 ohm
So as charge in the battery drops the analog input voltage to the ESP-12E drops. But I have a doubt about voltage divider wether to use voltage divider or something else for this project. Because voltage divider will consume power continuously to drain the battery and will cause the circuit inefficient. and I've also red that voltage divider is mostly used in high impedance circuits.
So is simple voltage divider suitable for this circuit or should I use some other DC-DC converter or regulator for converting 4.2V to 1V more efficiently to drain as much less possible power from battery itself to provide it to analog Input of ESP-12E?