Turn off UART and the power consumption does not decrease

[helen]

Excuse me:

                  Suppose I Initialize and turn on UART and the power consumption is 4mA，When I call app_uart_close()  the power consumption is 2mA,If I don't initialize UART at the beginning, the power consumption is only 1.5mA，Why does it take 500μA more power consumption to call this function than if I didn't initialize UART at the beginning?

[JONATHAN LL]

Hi,

What SDK are you using ?

Regards,
Jonathan

[helen]

The SDK version I using is nRF5_SDK_16.0.0_98a08e2.

[JONATHAN LL]

Hi,

There is a bug that will cause the app_uart_close() to not work correctly.  So you have to make sure that the UART is stopped before you call the app_uart_close(), and app_uart_close() should also wait for APP_UART_TX_EMPTY  to make sure the TX buffer is empty.

Here is a similar case: nRF52840 SDK16 - "app_uart_close()" cannot low current - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com) 

Regards,
Jonathan