High power consumption when softdevice enabled without advertising

[david]

Hello!

I am developing a bracelet product base on nrf52832.  I have a problem with softdevice's power consumption ,  when softdevice enabled,the power comsuption will rise about 500uA more than softdevice is not enabled.

  After I call  ble_stack_init with code below, power comsuption will rise about 500uA. It is without advertising at all.

static void ble_stack_init(void)
{
    ret_code_t err_code;

    err_code = nrf_sdh_enable_request();
    APP_ERROR_CHECK(err_code);

    // Configure the BLE stack using the default settings.
    // Fetch the start address of the application RAM.
    uint32_t ram_start = 0;
    err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
    APP_ERROR_CHECK(err_code);

    // Enable BLE stack.
    err_code = nrf_sdh_ble_enable(&ram_start);
    APP_ERROR_CHECK(err_code);

    // Register a handler for BLE events.
    NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
	
	
}

those 500uA seems abnormal ,why is it so high, how can i lower it?  thanks.

• SDK v 14.0
• softdevice version 5.0.0
• Using RELEASE configuration.

[MartinBL]

Hi,

500 uA sounds like the HF clock might be running constantly and there can be many reasons why. Some peripheral or driver, might e.g. have turned it on and forgotten to turn it off again after use. 

1. Are you using custom code or an example? Can you share the rest of it?
2. Are you developing on a development kit or a custom PCB?
3. Will I be able to run your code on a nRF52 DK kit and measure myself?
4. What low frequency clock source do you use?
5. Are you using the Logger library? It might help if you turn it off.