I’ve recently got a new multimeter with data logging capability. I did some measurements on tt-go t-beam and the lowest consumption, without a screen attached was 14-19mA this was node left idle for a few hours powered from battery ~4.1V with my second node powered off so it would wake or disturb the other node by sending anything, I presume in modem sleep? Active and possibly sending a packet about 97mA. Powered off via the pek(?) button, the one that’s connected to axp192, 50uA. These figures are quite close to what is in the spreadsheet
For comparison I have a simple app that deep sleep and wake up every so often and reads a bme280 sensor and send the readings, 197mA sending data, deep sleep 812uA, again this deep sleep value is close to what’s in the spreadsheet, the wake method is by timer only so no gpio active.
I was wondering what the voltage is the lowest esp32 go to when the battery is nearly empty, I have heard of people saying 2.8V is around the point where the esp32 stops working. I believe that the supported voltage range is 3.0 to 3.6V. I have tried axp.setDCDC1Voltage(3000); on my project to set 3.0V and it works fine. I am not sure if it save any power running the esp32 at 3.0V, I have heard people claim that it does, I didn’t notice, but I didn’t work out the average draw to see if its lower, if it is lower its not much. May be more prone to brownouts? By default axp192 shuts off the protect battery from over discharge at 2.9V (reg 31H) configurable in 0.1V steps from 2.6V to 3.3V. The LoRa radio sx127x operates between 1.8 and 3.7V according to datasheet, whether the voltage affects the transmit power IDK.