Truly ultra low power EPS32 module?

[zazas321]

Hey. I had a chance to try out different microcontrollers (ESP32, ESP32S3, STM32L031, NRF52832). Although I like Espressif MCU's a lot and use them for my personal projects as well we use them in our company for commercial projects, it seems to me that when it comes to ultra low power consumption, ESP32 is not a match for some STM32 and NRF52 microcontrollers that are intended to use for low power applications. Some of them consume <1uA deep sleep current, only about 1mA when CPU is idling and the initial startup current is only a few mA.

My best results with ESP32 FireBeetle module:

12uA deep sleep current
2mA auto light sleep when CPU is idling
Start up current when the module wakes up peaks to about 50mA


I wonder if we are going to get truly ultra low power ESP32 module at some point in the near future? What are your thoughts and experiences when it comes to ultra low power applications? Any thought or response is appreciated.

[bidrohini]

Hope ESP32 team will think over this issue.

[NickAllen]

I tried to use a Wemos D1 R32 in a low power application and found that the other components on the board consume far more current that the ESP32. In fact the D1 R32 used over 13ma in deep sleep mode due to the power supply components, the CH340 and an opamp! Looking at the component specs, it could have been over 30ma worst case. The DFRobot Firebeetle is the best I have found but also the Lolin32 Lite is also very good.

[JoeSensoric]

I have several ESP32-based battery-driven sensors working. In the ESP32-world the board is the main factor. Like NickAllen wrote, the DFRobot boards and some Lolin boards are good for that, I use the Lolin D32 (not "Pro") board.
A new DFRobot board with the ESP32-C6 looks good:
https://wiki.dfrobot.com/SKU_DFR1117_Beetle_ESP32_C6

Most of the power is needed when the communication parts are active. The C6 takes at least 94 mA when sending BLE telegrams. The new ESP32-H2 only needs 26 mA.

But there are devices on the market sending BLE advertising and using a CR2032 coin cell which run more than a year. So more very low power BLE hardware would be a nice addition to a future ESP32 controller.