Minimize power consumption of CC2640

Hi Thomas,

The instructions are in this app note for how to measure the ~1uA sleep current:

www.ti.com/.../swra478.pdf

 

Hi Thomas,

The link provided by Zahid Haq shows how to measure the current draw using BLE.

If you only want to measure the Standby current comment out everything in main() except for BIOS_start(). This should make TI RTOS start up and execute only its Idle thread which puts the device in Standby.

Regards,
Svend

Svend,

In our design, the device is transmitting beacon every 500mS.  Same beacon information.

The design is implemented on CC2541 and now we port the same design to CC2640.

We compare the current drawn of the two devices.

The TX, RX power of the CC2640 is much lower than the CC2541, but the current drawn during sleep time (between beacons) is much higher.

We think that the CC2640 cannot go to full sleep mode (where only timer is running).

Anything in the code that we need to check to assure the CC2640 go to sleep mode between beacons?

Thanks

I would suggest you to check if there is any current leakage on IO pins of CC2640.

We do not use any GPIO pin in this design. There is only one 100K resistor on the RESET pin.

Thomas,

I suggest you start by doing a test of your board by -only- having BIOS_start() in main and measure the current draw after ~10-15 seconds.
If the current draw is fine then there is something in software causing the increased current draw or preventing the device from going to Standby. Otherwise there is an issue with the board. Once we know what the cause of this is we can help out trying to find the root cause.

Also, please provide more details on your BLE SDK version, a schematic and info on what example project you are using to measure current draw.

Regards,
Svend

I am using simpleBLEperipheral.
The main programmed is masked off as shown below.
The current measure is ~1.4mA
Anything else I should do.

int main()
{
// PIN_init(BoardGpioInitTable);

#ifndef POWER_SAVING
/* Set constraints for Standby, powerdown and idle mode */
// Power_setConstraint(Power_SB_DISALLOW);
// Power_setConstraint(Power_IDLE_PD_DISALLOW);
#endif // POWER_SAVING

/* Initialize ICall module */
// ICall_init();

/* Start tasks of external images - Priority 5 */
// ICall_createRemoteTasks();

/* Kick off profile - Priority 3 */
// GAPRole_createTask();

// SimpleBLEPeripheral_createTask();

#ifdef FEATURE_OAD
{
uint8_t counter;
uint32_t *vectorTable = (uint32_t*) 0x20000000;
#if defined(__IAR_SYSTEMS_ICC__)
uint32_t *flashVectors = &__vector_table;
#elif defined(__TI_COMPILER_VERSION__)
uint32_t *flashVectors = &ti_sysbios_family_arm_m3_Hwi_resetVectors;
#endif //Compiler.

// Write image specific interrupt vectors into RAM vector table.
for(counter = 0; counter < 15; ++counter)
{
*vectorTable++ = *flashVectors++;
}
}
#endif //FEATURE_OAD

/* enable interrupts and start SYS/BIOS */
BIOS_start();

return 0;
}

Actually the current current measured is 480uA.

Hi Thomas,

If you still see a current that high it might be that the 32kHz XTAL does not start up properly. If this doesn't start up then the 32kHz system clock will continue to be derived from the 48MHz internal RC oscillator and the device will not power down.

Regards,
Svend

Do you define POWER_SAVING in your project?

Hi

i have used "Simplepheripheral sample code" from BLE stack, as follow and i have commented out everything and i run only BIOS(); still i am getting 4mA consumption in the device, but it should show some low power,, help me out!!!!

int main()
{
//HCI_EXT_SetSCACmd(40);

//#if defined( USE_FPGA )
// HWREG(PRCM_BASE + PRCM_O_PDCTL0) &= ~PRCM_PDCTL0_RFC_ON;
// HWREG(PRCM_BASE + PRCM_O_PDCTL1) &= ~PRCM_PDCTL1_RFC_ON;
//#endif // USE_FPGA

/* Register Application callback to trap asserts raised in the Stack */
//RegisterAssertCback(AssertHandler);

//PIN_init(BoardGpioInitTable);

//#ifdef CC1350_LAUNCHXL
// // Enable 2.4GHz Radio
// radCtrlHandle = PIN_open(&radCtrlState, radCtrlCfg);

//#ifdef POWER_SAVING
// Power_registerNotify(&rFSwitchPowerNotifyObj,
// PowerCC26XX_ENTERING_STANDBY | PowerCC26XX_AWAKE_STANDBY,
// (Power_NotifyFxn) rFSwitchNotifyCb, NULL);
//#endif //POWER_SAVING
//#endif //CC1350_LAUNCHXL
//
//#if defined( USE_FPGA )
// // set RFC mode to support BLE
// // Note: This must be done before the RF Core is released from reset!
// SET_RFC_BLE_MODE(RFC_MODE_BLE);
//#endif // USE_FPGA

// Enable iCache prefetching
// VIMSConfigure(VIMS_BASE, TRUE, TRUE);
////
//// // Enable cache
// VIMSModeSet(VIMS_BASE, VIMS_MODE_ENABLED);
//
//#if !defined( POWER_SAVING ) || defined( USE_FPGA )
// /* Set constraints for Standby, powerdown and idle mode */
// // PowerCC26XX_SB_DISALLOW may be redundant
// Power_setConstraint(PowerCC26XX_SB_DISALLOW);
// Power_setConstraint(PowerCC26XX_IDLE_PD_DISALLOW);
//#endif // POWER_SAVING | USE_FPGA
//
// /* Initialize ICall module */
// ICall_init();
//
// /* Start tasks of external images - Priority 5 */
// ICall_createRemoteTasks();
//
// /* Kick off profile - Priority 3 */
// GAPRole_createTask();
////
//SimpleBLEPeripheral_createTask();

/* enable interrupts and start SYS/BIOS */
BIOS_start();

return 0;
}

Hi Abraham,

Please see the application note Measuring Bluetooth Low Energy Powe Consumption ( www.ti.com/.../swra478b.pdf ).