Why is NodeMCU running on a low power battery?
The two immediate suspects are the power regulator, and the UART, as discussed in the forum here. The first step is to target the power regulator. The AMS1117 LDO draws a quiescent current of “typically” 5mA. To prevent this, it may be sufficient to lift just pin 1. However, I chose to remove the whole chip to free up space for later.
How can I save power with NodeMCU without LDO?
Without the LDO, I measured a saving of 3mA. Now for the biggest saving – to disable the USB UART. This can be done with reference to the NodeMCU schematic by cutting power to pins 6 and 7. In practice this means cutting a track with an X-Acto knife under the best magnification you can find, and with steady hands.
How much power does NodeMCU use in deep sleep?
Unfortunately, with all this added convenience comes the drawback of added power consumption, which continues even when the ESP8266 is in deep sleep. I measured 18mA to the NodeMCU board while the ESP8266 was in deep sleep mode – orders of magnitude more power hungry than I was looking for.
Which is ESP32 breakout board for second sensor node?
For the second sensor node I chose a different ESP32 breakout board which has a battery connector and charger on board. The battery lifetime test with this ESP32 is still ongoing. What is missing on this ESP32 breakout board is the LoRa module. To get the LoRa functionality to this board, we need to connect an external LoRa module.
Is the SparkFun ESP32 sensor node battery powered?
The first one I used for a sensor node is the Sparkfun ESP32 LoRa module. It is actually not the best one if you want to setup a battery powered sensor node, because it does not have a connector for a battery. But it is easy to use because it has the LoRa module integrated in its board. The Sparkfun ESP32 with a LoRa module on the board.
How long does battery last on Lora sensor node?
It is not the best selection when it is about low power consumption, but it can be tuned to reach quite good battery lifetimes (>>7 days from a 1600mAh LiIon battery). In the test setup I used three different ESP32 modules.