Xiao nRF52840 still too high consumption

[Radek]

Hi together,

I have very elementar project, measuring temperature by SHT31 (I2C) and advertising measured value via BLE at XIAO nRF52840. Im using ArduinoBLE.h library and powering that from one 18650 via battery pads. Everything works fine except of power consumption - minimum I got is some 6mA, which is far too much than expected uA. I set advertising interval to 5 sec (via BLE.setAdvertisingInterval) and temperature reading each 10s with delay (10000) command. Even when nRF52840 is doing nothing, consumtion cant get under those 6mA. The same result, when I disconnect that SHT31 sensor for to ensure myself, sensor is not responsible for this high total consumption. I hava no idea what to do to get those “magic” uA instead of mA.

[msfujino]

You might find the link below helpful.

System_ON_Sleep of XIAO BLE

System_OFF_Sleep (Deep Sleep) is used to significantly reduce current consumption, but requires an external trigger for wake-up. On the other hand, System_ON_Sleep can easily woken up using the built-in RTC interrupt. In a project that periodically sends data from a peripheral to the central, I experimented with System_On_Sleep to see how much current consumption of a peripheral XIAO could be reduced. In System_ON_Sleep, the CPU sleeps by the WFI() command, but during sleep, it seems to repeate…