Power consumption nRF52840-DK in sleep mode while using UART

[K_H]

Hello,

I'm trying to get sleep mode working on a nRF52840-DK with Zephyr or Mbed OS while using UART.

It is possible to achieve low current consumption in sleep mode (~3µA) while using I2C or SPI. The current remains at ~900µA in sleep mode when I use UART. I've even tried to delete the serial object before entering sleep mode without any effect.

Is it possible to achieve a low current consumption (<10µA) with UART using Mbed OS or Zephyr? UART doesn't have to be enabled during sleep mode.

Thank You!

[Jared]

Hi,

Is the HFCLK still running? What function are you using to set it in sleep mode, and could you share your project?

regards

Jared