High power consumption in system OFF mode using xiao nrf52840 ble

[Juan Lopez]

Hello, recently I bought the Seeed XIAO nrf52840 because I read in the datasheets the power consumption of the microcontroller is 400 nA typical in SYSTEM OFF mode without RAM retention and peripherals and 3.3V

However, when I measure the power consumption using the Power Profiler Kit II, the consumption is of 10uA running the following code:

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void setup() {
  NRF_UART0->ENABLE = 0;

  /*medicion de temperatura usando registro del sensor*/
  int32_t temp;
  NRF_TEMP->TASKS_START = 1;
  while(NRF_TEMP->EVENTS_DATARDY == 0){}
  temp = NRF_TEMP->TEMP;
  NRF_TEMP->TASKS_STOP = 1;

  /*deshabilitar ADC y apagar secciones de RAM*/
  NRF_SAADC->TASKS_STOP = 1;
  NRF_SAADC->ENABLE = 0;

  NRF_NFCT->TASKS_GOSLEEP = 1;
  NRF_NFCT->ENABLE = 0;

  //power of RAM sections to avoid consumption in system OFF
  for(size_t i = 0; i<9; i++){
    NRF_POWER->RAM[i].POWER = 0;
  }

  // Put the device in system off mode
  NRF_POWER->SYSTEMOFF = 1;
}

void loop() {
  // Empty loop, as the device is in system off mode
}

The code is loaded from Arduino IDE. If I try to flash the equivalent code from VSCode using the nRF Connect SDK 2.6.1 extension, the system doesn't even go into SYSTEM OFF mode.

These are the measurements I obtained. Consumption averages at 10.76uA with minimums around 10.12uA and I assume the spikes are caused by an internal regulator.

To measure the consumption, I am using source mode with output enabled connecting V_out PPK2 to the 3.3V pin of the SeeedIA and bothNDs connected together Everything is on a breadboard.

I would like to the source of this high power consumption. Is the method I am using to power off peripherals effective, or could they still be on?

I am aiming to reach500nA if, but powering off peripherals doesn't seem to impact the consumption in any meaningful way.