Current consumption of STM32L4R5 in low power modes not as per datasheet

SD0509 · ‎2024-02-14

I'm attempting to enable the Stop mode on the STM32L4R5ZIP, but it appears to significantly deviate from the specifications outlined in the datasheet, exhibiting a higher current consumption ranging from 7 to 9 mA in both sleep and stop modes.
Even after setting all free pins to default mode, deactivating all GPIOs, the power consumption remains consistent. I have experimented with both FreeRTOS and a non-FreeRTOS project, yet I consistently observe a 7mA current consumption in STOP Low-Power modes.

In the FreeRTOS project, I implemented tickless mode with the following code snippet:

void PreSleepProcessing(uint32_t ulExpectedIdleTime)

{

/* Called by the kernel before it places the MCU into a sleep mode because

configPRE_SLEEP_PROCESSING() is #defined to PreSleepProcessing().

NOTE: Additional actions can be taken here to get the power consumption

even lower. For example, peripherals can be turned off here, and then back

on again in the post sleep processing function. For maximum power saving

ensure all unused pins are in their lowest power state. */

HAL_SuspendTick();

HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 0x801, RTC_WAKEUPCLOCK_RTCCLK_DIV16);

__disable_irq();

__HAL_RCC_USB_OTG_FS_CLK_DISABLE();

__HAL_RCC_GPIOE_CLK_DISABLE();

__HAL_RCC_GPIOC_CLK_DISABLE();

__HAL_RCC_GPIOF_CLK_DISABLE();

__HAL_RCC_GPIOH_CLK_DISABLE();

__HAL_RCC_GPIOA_CLK_DISABLE();

__HAL_RCC_GPIOB_CLK_DISABLE();

__HAL_RCC_GPIOG_CLK_DISABLE();

__HAL_RCC_GPIOD_CLK_DISABLE();

HAL_PWREx_DisableVddIO2();

//STOP2 MODE

HAL_PWREx_EnterSTOP2Mode(PWR_SLEEPENTRY_WFI); /

}

void PostSleepProcessing(uint32_t ulExpectedIdleTime)

{

/* Called by the kernel when the MCU exits a sleep mode because

configPOST_SLEEP_PROCESSING is #defined to PostSleepProcessing(). */

/* WAKE UP WITH RTC */

HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);

HAL_RCC_DeInit();

__enable_irq();

/* resume systicks */

HAL_ResumeTick();

SystemClock_Config();

__HAL_RCC_GPIOE_CLK_ENABLE();

__HAL_RCC_GPIOC_CLK_ENABLE();

__HAL_RCC_GPIOF_CLK_ENABLE();

__HAL_RCC_GPIOH_CLK_ENABLE();

__HAL_RCC_GPIOA_CLK_ENABLE();

__HAL_RCC_GPIOB_CLK_ENABLE();

__HAL_RCC_GPIOG_CLK_ENABLE();

__HAL_RCC_GPIOD_CLK_ENABLE();

}

I would highly appreciate any insights or suggestions to minimize the current consumption in this scenario.

Andrew Neil · ‎2024-02-15

@waclawek.jan wrote:
It may be *one* of the explanation - others brought up valid points, too.

It explains the current being in the many-mA range.

I don't think the other things would explain that much excess ?

Andrew Neil · ‎2024-02-15

@SD0509 wrote:
I removed the jumper JP5 (labelled IDD) on the board and connected a multimeter in series to measure the MCU consumption.

Remember that's still going to measure leakage to other things on the board - in particular, the ST-Link.

There will be directions in the User Manual on other links that will need to be broken to minimise the "stray" currents.

You will also need to check the schematics carefully - sometimes the UM text does not tell the whole story...
☹️

(but these should all be on the order of uA - shouldn't account for 7mA!)

SD0509 · ‎2024-02-15

void PreSleepProcessing(uint32_t ulExpectedIdleTime)
{
	/* Called by the kernel before it places the MCU into a sleep mode because
	  configPRE_SLEEP_PROCESSING() is #defined to PreSleepProcessing().

	  NOTE:  Additional actions can be taken here to get the power consumption
	  even lower.  For example, peripherals can be turned off here, and then back
	  on again in the post sleep processing function.  For maximum power saving
	  ensure all unused pins are in their lowest power state. */
	HAL_DBGMCU_EnableDBGStopMode();
	//__disable_irq();
	LP_GPIO_Init();

       HAL_SuspendTick();
       HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 0x500B, RTC_WAKEUPCLOCK_RTCCLK_DIV16);

	//STOP2 MODE
	HAL_PWREx_EnterSTOP2Mode(PWR_SLEEPENTRY_WFI);

}

void PostSleepProcessing(uint32_t ulExpectedIdleTime)
{
	/* Called by the kernel when the MCU exits a sleep mode because
	  configPOST_SLEEP_PROCESSING is #defined to PostSleepProcessing(). */

	/* WAKE UP WITH RTC */
	//HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);

	MX_GPIO_Init();
	//__enable_irq();
	//
	/* resume systicks */
	HAL_ResumeTick();
	SystemClock_Config();

}

After configuring pins to Analog mode in LP_GPIO_Init function and adding HAL_DBGMCU_EnableDBGStopMode the power consumption dropped to 0.4mA.

SD0509 · ‎2024-02-20

I'm not sure how to do it. Could you provide me with some insight?

waclawek.jan · ‎2024-02-20

I meant:

- disconnect debugger

- remove power

- connect power

JW

SD0509 · ‎2024-02-21

Thank you all ! I appreciate all your suggestions. The consumption has significantly decreased frome 7mA to 250uA.
But I'm still puzzled by this value that differs from what is indicated in the datasheet. Do you notice anything else that might be causing this issue?
Here's my clock configuration:

and this is my code snippet:

void PreSleepProcessing(uint32_t ulExpectedIdleTime)
{
	/* Called by the kernel before it places the MCU into a sleep mode because
	  configPRE_SLEEP_PROCESSING() is #defined to PreSleepProcessing().

	  NOTE:  Additional actions can be taken here to get the power consumption
	  even lower.  For example, peripherals can be turned off here, and then back
	  on again in the post sleep processing function.  For maximum power saving
	  ensure all unused pins are in their lowest power state. */
	HAL_DBGMCU_DisableDBGStopMode();
	LP_GPIO_Init();
	HAL_SuspendTick();
    HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 0x500B, RTC_WAKEUPCLOCK_RTCCLK_DIV16);
	//STOP2 MODE
	HAL_PWREx_EnterSTOP2Mode(PWR_SLEEPENTRY_WFI);
}

void PostSleepProcessing(uint32_t ulExpectedIdleTime)
{
	/* Called by the kernel when the MCU exits a sleep mode because
	  configPOST_SLEEP_PROCESSING is #defined to PostSleepProcessing(). */

	/* WAKE UP WITH RTC */
	HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
	MX_GPIO_Init();
	HAL_ResumeTick();
	SystemClock_Config();
}

void LP_GPIO_Init(void)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOF_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOG_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  HAL_PWREx_EnableVddIO2();

  /*Configure GPIO pins : PE2 PE3 PE4 PE5
                           PE6 PE7 PE8 PE9
                           PE10 PE11 PE12 PE13
                           PE14 PE15 PE0 PE1 */
  GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5
                          |GPIO_PIN_6|GPIO_PIN_7|GPIO_PIN_8|GPIO_PIN_9
                          |GPIO_PIN_10|GPIO_PIN_11|GPIO_PIN_12|GPIO_PIN_13
                          |GPIO_PIN_14|GPIO_PIN_15|GPIO_PIN_0|GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);

  /*Configure GPIO pins : PC13 PC14 PC15 PC0
                           PC1 PC2 PC3 PC4
                           PC5 PC6 PC7 PC8
                           PC9 PC10 PC11 PC12 */
  GPIO_InitStruct.Pin = GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15|GPIO_PIN_0
                          |GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3|GPIO_PIN_4
                          |GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7|GPIO_PIN_8
                          |GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11|GPIO_PIN_12;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

  /*Configure GPIO pins : PF0 PF1 PF2 PF3
                           PF4 PF5 PF6 PF7
                           PF8 PF9 PF10 PF11
                           PF12 PF13 PF14 PF15 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
                          |GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7
                          |GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
                          |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);

  /*Configure GPIO pins : PH0 PH1 PH3 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_3;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

  /*Configure GPIO pins : PA0 PA1 PA2 PA3
                           PA4 PA5 PA6 PA7
                           PA8 PA9 PA10 PA11
                           PA12 PA15 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
                          |GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7
                          |GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
                          |GPIO_PIN_12|GPIO_PIN_15;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pins : PB0 PB1 PB2 PB10
                           PB12 PB13 PB14 PB15
                           PB3 PB4 PB5 PB6
                           PB7 PB8 PB9 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_10
                          |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15
                          |GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6
                          |GPIO_PIN_7|GPIO_PIN_8|GPIO_PIN_9;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pins : PG0 PG1 PG2 PG3
                           PG4 PG5 PG6 PG7
                           PG8 PG9 PG10 PG11
                           PG12 PG13 PG14 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
                          |GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7
                          |GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
                          |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOG, &GPIO_InitStruct);

  /*Configure GPIO pins : PD8 PD9 PD10 PD11
                           PD12 PD13 PD14 PD15
                           PD0 PD1 PD2 PD3
                           PD4 PD5 PD6 PD7 */
  GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
                          |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15
                          |GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
                          |GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;

  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  __HAL_RCC_GPIOE_CLK_DISABLE();
  __HAL_RCC_GPIOC_CLK_DISABLE();
  __HAL_RCC_GPIOF_CLK_DISABLE();
  __HAL_RCC_GPIOH_CLK_DISABLE();
  //__HAL_RCC_GPIOA_CLK_DISABLE();
  __HAL_RCC_GPIOB_CLK_DISABLE();
  __HAL_RCC_GPIOG_CLK_DISABLE();
  __HAL_RCC_GPIOD_CLK_DISABLE();
}

Andrew Neil · ‎2024-02-21

@SD0509 wrote:
I'm still puzzled by this value that differs from what is indicated in the datasheet.

Again, the datasheet covers just the chip itself - it cannot take anything outside the chip into account.

It also knows nothing of your application.

@SD0509 wrote:
anything else that might be causing this issue?

See: https://community.st.com/t5/stm32-mcus-products/current-consumption-of-stm32l4r5-in-low-power-modes-not-as-per/m-p/640406/highlight/true#M235685

Andrew Neil · ‎2024-02-21

Another thought:

@SD0509 wrote:

	  NOTE:  Additional actions can be taken here to get the power consumption
	  even lower.  For example, peripherals can be turned off here, and then back
	  on again in the post sleep processing function.  For maximum power saving
	  ensure all unused pins are in their lowest power state. */

@SD0509 wrote:
Do you notice anything else that might be causing this issue?

You've done the bit about "ensure all unused pins are in their lowest power state", but I don't see you turning off any peripherals...?

🤔

SD0509 · ‎2024-02-21

At the project's creation, I didn't initialize the pins to their default mode. Moreover, I've disabled all AHB1, AHB2, APB1, and APB2 peripheral clocks, yet the power consumption remains unchanged.

Andrew Neil · ‎2024-02-21

Back to this post:

https://community.st.com/t5/stm32-mcus-products/current-consumption-of-stm32l4r5-in-low-power-modes-not-as-per/m-p/640406/highlight/true#M235685

are you sure you've isolated everything to be sure that what you're measuring in just the STM32L4R5 and nothing else?