CC2640 - Sensor Controller power consumption

Hi everyone,

I'm using the sensor controller of my CC2640 to drive a step-by-step motor. I need to use ADC and delay insertions, and user the less power as possible. 

But when I start the sensor controller, it already use 600uA without doing anything :

// Initialisation code
U16 k = 0;
do {
    fwDelayUs(10000, FW_DELAY_RANGE_100_MS);
    k = k + 1;
}while(k != 250);

fwScheduleTask(1);

The sensor controller should use 8.2uA / Mhz, so around 200uA at 24Mhz, and even at 12Mhz it still use 550uA. I show you the Init / start / stop functions I use. Thanks in advance for your help

/* Initialize the Sensor Controller  */
SCIF_RESULT_T SensorController_init()
{
	// Enable power domains
	PRCMPowerDomainOn(PRCM_DOMAIN_PERIPH);
	while (PRCMPowerDomainStatus(PRCM_DOMAIN_PERIPH) != PRCM_DOMAIN_POWER_ON);

	// Enable peripheral clocks
	PRCMPeripheralRunEnable(PRCM_PERIPH_GPIO);
	PRCMLoadSet();
	while (!PRCMLoadGet());

    scifOsalEnableAuxDomainAccess();						// Prevent AUX from powering down
	scifOsalInit();											// Initializes the OSAL
	scifOsalRegisterTaskAlertCallback(scTaskAlertCallback);	// Register callback method for Task alert

	//*Set activ mode in low frequency
	HWREG(AUX_WUC_BASE + AUX_WUC_O_CLKLFREQ) = 1;
	while(HWREG(AUX_WUC_BASE + AUX_WUC_O_CLKLFACK) != 1);

	HWREG(AUX_WUC_BASE + AUX_WUC_O_CLKLFREQ) = 0;
	while(HWREG(AUX_WUC_BASE + AUX_WUC_O_CLKLFACK) != 0);

	// Use less than 24Mhz
	HWREG(AON_WUC_BASE + AON_WUC_O_AUXCLK) |= AON_WUC_AUXCLK_SCLK_HF_DIV_DIV4 ;

	return scifInit(&scifDriverSetup);						// Enable the driver
}

 /* Start one time init-execute-terminate session  */
SCIF_RESULT_T SensorController_start_once()
{
	scifStartRtcTicksNow(0x100);	// Start ticks (for alert events)	bit 15:0 -> 1/65536 of seconds, about 100us

    // Open the AUX I/O latches, which have undefined value after power-up. AUX_AIODIO will by default
    // drive '0' on all I/O pins, so AUX_AIODIO must be configured before IOC
    HWREG(AUX_WUC_BASE + AUX_WUC_O_AUXIOLATCH) = AUX_WUC_AUXIOLATCH_EN_TRANSP;

	//scifTaskResourceInit();		  								// Start I/O
	return scifCtrlTasksNbl(BV(SCIF_MOTOR_CONTROL_TASK_ID), 0x07);	// Init and execute sensor (not termintae)
}

 /* Stop ticks and Sensor Controller task */
SCIF_RESULT_T SensorController_stop()
{
	SCIF_RESULT_T res = SCIF_SUCCESS;

	res = scifStopTasksNbl(BV(SCIF_MOTOR_CONTROL_TASK_ID));
	if(res == SCIF_SUCCESS)
	{
		while(scifWaitOnNbl(0) != SCIF_SUCCESS);

		scifStopRtcTicks();
	    // Wait until the Sensor Controller is idle (it might still be running, though not for long)
	    while (!(HWREG(AUX_SCE_BASE + AUX_SCE_O_CPUSTAT) & AUX_SCE_CPUSTAT_SLEEP_M));

		scifTaskResourceUninit();	// Disable I/O
	}
	return res;
}

/* Task Main function : */
if(SCIF_SUCCESS == SensorController_start_once())
{
	// Wait semaphore
	Semaphore_pend(Semaphore_handle(&semScTaskAlert), BIOS_WAIT_FOREVER);
	scifClearAlertIntSource();

	// Stop sensor controller
	scifAckAlertEvents();

	while(SensorController_stop() != SCIF_SUCCESS);
}