Current Consumption of STM32L-DISCOVERY in low Power Modes

[aa_talaat]

Posted on August 11, 2013 at 19:23

Hi,

I am using the STM32L-DISCOVERY evaluation board, and I made JP1 off as per the below instructions from the evaluation board user manual:

 

JP1 OFF: the STM32L152 is directly powered, IDD measurement circuit is bypassed.

 

Note: When jumper JP1 is removed the current consumption of the STM32L152 can be measured by connecting an ammeter between jumper pin 1 and pin 2 of JP1.

I am using the following code and measure the current consumed using an Ammeter. I wrote on the right side comment with the actual current consumed:

int main(void)

{

    /* Configure PB6 and PB7 as output */

    GPIO_Config();

    /* Configure PA0 in interrupt mode */

    EXTI0_Config();

    /* Infinite loop */

  while (1)

  {

//      PWR_EnterSleepMode(PWR_Regulator_LowPower,PWR_SLEEPEntry_WFI);    // 2.3mA

//      PWR_EnterSTANDBYMode();        // 0.7mA

      PWR_EnterSTOPMode(PWR_Regulator_LowPower,PWR_STOPEntry_WFI);    // 0.7mA

  }

  return 0;

}

These value are far from the expected values that are documented in the STM32L documentation which I expect to be few micro amps in stop and standby modes.

• Is there any other part of the evaluation board that is consuming this current?
• Is there something wrong in my code?

I am coming from an MSP430 background which consumes 2-3uA in its equivalent low power mode.

Thank you.

[Tesla DeLorean]

Posted on August 12, 2013 at 01:07

        /* Disable PVD */

        PWR_PVDCmd(DISABLE);

        /* Enable The ultra Low Power Mode */

        PWR_UltraLowPowerCmd(ENABLE);

Clocks?

GPIO's in Analog Input (turns off outputs, turns off input schmitt trigger)? Driving stuff outside the core is the primary cause of current draw.

The examples for switching into low power modes seem more complicated than what you have presented.