18 µA Higher Current Consumption With Full Firmware Package

[Romal Patel]

Hello Nordic Team,

I am working with an nRF52840 on a custom hardware board and investigating the current consumption in idle condition.

I have tested the same hardware with two different firmware configurations:

• Application + SoftDevice only: approximately 147 µA
• Full firmware/package: approximately 165 µA

This results in an additional current consumption of approximately 18 µA when the full package is programmed.

The hardware and measurement setup are the same for both tests. The main difference is the firmware/package being loaded.

I would like to understand what could cause this additional ~18 µA consumption.

The measured values are repeatable on the same custom board.

Hardware: Custom nRF52840 board
MCU: nRF52840
Application + SoftDevice current: ~147 µA
Full package current: ~165 µA
Difference: ~18 µA

What would be the recommended approach to isolate the source of this additional 18 µA?

Thank you.

[Vidar Berg]

Hello,

Is the current you are measuring isolated to the nRF, or is there external circuitry on your custom board that is included in the measurement? Reason for asking is that 147 uA is already well above the 3-4uA typical sleep current of the chip.

If the measurement was not isolated to the nRF, a possible explanation for the discrepancy could be that you have configured a pin interrupt using GPIOTE in event mode.

Best regards,

Vidar