Current Consumption when using timer and scheduler alongwith nrf_pwr_mgmt_run().

Question

Hi Everyone, 
 I am using the following peripherals in my project 
 2 UARTE. 
 2 ADC 
 1 TWI 
 BLE 
 GPIOTE interrupt for 2 buttons 
 TWI and ADC and BLE and GPIOTE are not consuming more current when there are no events (when its in sleep mode, current is around 240uA) 
 However , when i initialise the 2 UART and also uninit both of them , the current doesn't come below 1.1mA , Is it Normal? 
 If not , how can i set up the UART part to use 2 UARTEs without consuming much current in the sleep mode , when there are no events occuring. 
 I have a custom PCB using nrf52840 , SDK 15.0 And Segger Embedded Studio IDE.

Einar Thorsrud · Accepted Answer

The addresses for disabling UARTE0 and UARTE1 are different (0x40002FFC and 0x40028FFC). These registers are undocumented as they should not normally be used, but are needed as a workaround in this case. 
 Please refer to the code snippet in my previous answer for a full example that demonstrates how you can use both in low power mode. To extract just the main point you should use this code (I include the call to nrf_serial_uninit() for completeness): 
 // Disable UARTs to reduce current consumption
 nrf_serial_uninit(&serial0_uarte);
 nrf_serial_uninit(&serial1_uarte);

 // Workaround current consumption issue by power cycling the UART peripherals
 *(volatile uint32_t *)0x40002FFC = 0; // Power down UARTE0
 *(volatile uint32_t *)0x40002FFC; //
 *(volatile uint32_t *)0x40002FFC = 1; // Power on UARTE0 so it is ready for next time

 *(volatile uint32_t *)0x40028FFC = 0; // Power down UARTE1
 *(volatile uint32_t *)0x40028FFC; //
 *(volatile uint32_t *)0x40028FFC = 1; // Power on UARTE1 so it is ready for next time

Current Consumption when using timer and scheduler alongwith nrf_pwr_mgmt_run().

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