Power consumption is too high

[Sergio T]

I am using the PCA10028 to connect to my board and use Segger embedded studio. I am unable to bring my power consumption below 1 mA.

To exclude my hardware from the equation, I decided to connect the EEPROM I´m using (24LC16) and one key to the PCA10028 board and use the nRF current measurement feature. I soldered a 22 Ohm resistor on R6 and loaded my program into it. 

The program is very simple: if key is ON I have BLE advertising and all runs.

If key is OFF, then I stop BLE advertising and only keep my app_timer running on RTC1. I tried also stopping the timer and the result is the same. I get 1 mA consumption.

I tried performing NRF_POWER->SYSTEMOFF = 1; instruction but the controller doesn't stop (I made an endless loop with this instruction and toggle of a LED) and the code just ignores the command and continues running, even if I don't connect the board to the PC (use then a battery for supply).

I tried also NRF_POWER->TASKS_LOWPWR = 1; but it also doesn't work.

I tried __WFE(); __SEV(); and even __WFI(); but none seams to work. 

What am I doing wrong?

[Sergio T]

For information, here is my main loop:

//-------------------------------------
/**@brief Application main function.
 */
//-------------------------------------
int main(void)
{
    uint32_t err_code;

// ---- Initialize ckock timer ----
    
    APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_OP_QUEUE_SIZE, false);
    err_code = app_timer_create(&real_time_clock_id, APP_TIMER_MODE_REPEATED, rtc_handler);
    app_timer_start(real_time_clock_id, 32767, false);
    
// ---- Initialize kernel timer ----
    err_code = app_timer_create(&kernel_clock_id, APP_TIMER_MODE_REPEATED, kernel_handler);
// ----
#ifdef USE_BLE
    ble_stack_init();
    gap_params_init();
    services_init();
    advertising_init();
    conn_params_init();
#endif
//    configure_ram_retention();
#ifdef DEBUG_PRINT
    printf("\r\nUART Start after RESET!\r\n");
    printf("BT Disconnected");
    printf("\r\n");
#endif
    InitIo();
    CheckWarmCold();      // chek if EEPROM was initialized
    ClearRxString();      // clear BLE receive buffer
    f_key_was_on = 0;
    f_power_is_on = 0;    
    InitIo();             // configure ports
    for (;;)
      {
      power_manage();
      if (f_power_is_on)
        {
        if (f_data_rx)
          {
          f_data_rx = 0;
#ifdef DEBUG_PRINT
          printf("RX: ");
          printf(rx_string);
          printf("\r\n");
#endif
          if (ParseMessage())           // parse command to rx_data[]
            {
            ClearRxString();            // clear rx_buffer for next communication
            ExecuteMessage();
            }
          else
            ClearRxString();            // message invalid: clear rx_buffer for next communication
          }
        if (f_data_tx)
          {
          f_data_tx = 0;
#ifdef DEBUG_PRINT
          printf("TX: ");
          printf(tx_string);
          printf("\r\n");
#endif
          ble_nus_string_send(&m_nus, tx_string, tx_string_len);
          }
        }
      CheckPowerKey();                // check power key
      if (f_power_is_on)
        {
        CheckScheduling();
        UpdatePumpOperation();
        Timers();
        UpdateLed();
        }
      }
}

[Sergio T]

and the Check Power Key routine:

//-------------------------------------
void CheckPowerKey(void)
{
  if (f_key_was_on)
    {
#ifdef DEMO_BOARD
    if (nrf_gpio_pin_read(K_PWR) || !nrf_gpio_pin_read(PDN))
#else
    if (!nrf_gpio_pin_read(K_PWR) || !nrf_gpio_pin_read(PDN))
#endif
      {
      f_key_was_on = 0;   // key changed ON -> OFF
      }
    else // Key is On and not PDN: => switch on if was off
      {
      if (!f_power_is_on)
        {
        f_power_is_on = 1;
        PowerOffToOn();
        first_minute = 60;
        StartBLE();       // start BLE and kernel_int
        RebuildActionSequence();
//        ReloadOnPeriod();
//        ReloadOffPeriod();
        if (!po_on_period)
          po_on_period = TEST_ON_PERIOD;
        }
      }
    }
  else // f_key_was_on = 0
    {
#ifdef DEMO_BOARD
    if (!nrf_gpio_pin_read(K_PWR) && nrf_gpio_pin_read(PDN))
#else
    if (nrf_gpio_pin_read(K_PWR) && nrf_gpio_pin_read(PDN))
#endif
      {
      f_key_was_on = 1;       // key changed OFF -> ON
      }
    else // Power key is OFF: => switch off if it was on
      {
      if (f_power_is_on)
        {
        StopBLE();       // stop BLE and kernel_int
        f_power_is_on = 0;
        first_minute = 0;
        PowerOnToOff();
        }
      }
    }
}

[Sergio T]

Here is the rest:

//-------------------------------------
void StopBLE(void)
{
#ifdef USE_BLE
  if (f_bt_connected)
    bsp_event_handler(BSP_EVENT_DISCONNECT);
  advertising_stop();
#endif
  app_timer_stop(kernel_clock_id);
  InitIo();                       // set IO to minimum consumption
}
//-------------------------------------
//
//-------------------------------------
void StartBLE(void)
{
#ifdef USE_BLE
  ble_advertising_start(BLE_ADV_MODE_FAST);
#endif
  app_timer_start(kernel_clock_id, 327, false);
  InitIo();                       // set IO to minimum consumption
}
//-------------------------------------
//
//-------------------------------------
void PowerOnToOff(void)
{
  nrf_gpio_pin_set(LED);
  nrf_gpio_pin_set(P_ON);
  i2c_init();
  app_timer_stop(real_time_clock_id);       // stop RTC1 - also clears COUNTER
}
//-------------------------------------
//
//-------------------------------------
void PowerOffToOn(void)
{
  lword seconds_elapsed;
  
  seconds_elapsed = NRF_RTC1->COUNTER;
  app_timer_start(real_time_clock_id, 32767, false);
}

[Sergio T]

Another thing: if I hold the controller in RESET (on the PCA10028) I have 1 mA consumption!

[Sergio T]

I forgot to mention: I am using soft_device 12 and I can say that it is the BLE soft_device that is consuming this power. So I think the answer to my problem could be quite simple:
How can I switch off the complete BLE before going into low power consumption?