2.17 mA when sleeping

[sijohans]

Hello,

I'm having trouble with my nRF52. The power consumption is around 2.17 mA when sleeping. I'm using the softdevice 4.0.2 enabled and using the sd_app_evt_wait and turning off the dcdc when sleeping.

uint32_t bsp_evt_wait( void )
{
    uint32_t ret_code = 0;
    ret_code |= bsp_dcdc_off();
    ret_code |= sd_app_evt_wait();
    ret_code |= bsp_dcdc_on();
    return ret_code;
}

I've looked at some examples and my setup seems to be quite similar. I also tried to flash the ble_app_uart and the power consumption was approximately the same.

The peripherals/libraries i use are: app_uart app_gpiote nrf_drw_wdt

I'm also realizing a real time clock using the RTC2 and TIMER2 with PPI. I'm advertising at an interval of 160ms.

I did this:

• Disable the advertising, then we should sleep "all the time". This didn't affect the "static" power consumption.

However, when i disable the UART i notice that the power consumption drops to approximately 16,6 uA (don't know the accuracy of the measurement instrument).

Disabling of GPIOTE, WDT or my real time clock didn't affect the power consumption noticeable.

Edit: I found this: devzone.nordicsemi.com/.../

I think it's strange that the UART peripheral uses that much current.

Any suggestions?

This is my latest discoveries:

If i don't enable uart: 18uA If i enable uart: 2.42mA If i enable uart and then disable (app_uart_init, app_uart_close): 26uA.

Have been testing writing to the registers but i can never reach the level if i never enable the uart.

[ovrebekk]

Hi

Could you share the code you used to test this? When the UART is active, and in RX mode, the current consumption will be quite high since the regulators and clocks need to be running all the time. That said, it should be possible to return to a proper low power state when you disable the UART RX again.