NUCLEO-L073RZ; Reach lowest power consumption in STOP MODE w/ RTC

[JAvil.3]

#include "main.h"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
 
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
 
/* USER CODE END PTD */
 
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
 
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
RTC_HandleTypeDef hrtc;
 
/* USER CODE BEGIN PV */
 
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_RTC_Init(void);
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
 
  /* USER CODE END 1 */
 
  /* MCU Configuration--------------------------------------------------------*/
 
  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();
 
  /* USER CODE BEGIN Init */
 
  /* USER CODE END Init */
 
  /* Configure the system clock */
  SystemClock_Config();
 
  /* USER CODE BEGIN SysInit */
 
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_RTC_Init();
  /* USER CODE BEGIN 2 */
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
	  HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
	  __HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);
	  HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);
    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}
 
/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
 
  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
 
  /** Configure LSE Drive Capability
  */
  HAL_PWR_EnableBkUpAccess();
  __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);
 
  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE|RCC_OSCILLATORTYPE_MSI;
  RCC_OscInitStruct.LSEState = RCC_LSE_ON;
  RCC_OscInitStruct.MSIState = RCC_MSI_ON;
  RCC_OscInitStruct.MSICalibrationValue = 0;
  RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_5;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
 
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC;
  PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
  /* Enable Power Control clock */
  __HAL_RCC_PWR_CLK_ENABLE();
 
  HAL_PWR_DisablePVD();
  HAL_RCCEx_DisableHSI48_VREFINT();
}
 
/**
  * @brief RTC Initialization Function
  * @param None
  * @retval None
  */
static void MX_RTC_Init(void)
{
 
  /* USER CODE BEGIN RTC_Init 0 */
 
  /* USER CODE END RTC_Init 0 */
 
  /* USER CODE BEGIN RTC_Init 1 */
 
  /* USER CODE END RTC_Init 1 */
 
  /** Initialize RTC Only
  */
  hrtc.Instance = RTC;
  hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
  hrtc.Init.AsynchPrediv = 127;
  hrtc.Init.SynchPrediv = 255;
  hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
  hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
  hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
  hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
  if (HAL_RTC_Init(&hrtc) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN RTC_Init 2 */
  HAL_RTCEx_DeactivateTimeStamp(&hrtc);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_1);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_2);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_3);
  HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
  HAL_RTC_DeactivateAlarm(&hrtc, RTC_ALARM_A);
  HAL_RTC_DeactivateAlarm(&hrtc, RTC_ALARM_B);
  /* USER CODE END RTC_Init 2 */
 
}
 
/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
 
  __HAL_RCC_PWR_CLK_ENABLE();
  	  /* Enable Ultra low power mode */
  HAL_PWREx_EnableUltraLowPower();
  	  /* Enable the fast wake up from Ultra low power mode */
  HAL_PWREx_EnableFastWakeUp();
 
  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
 
/*  Configure GPIO pin Output Level
  HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_RESET);
 
  Configure GPIO pin : B1_Pin
  GPIO_InitStruct.Pin = B1_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_IT_FALLING;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);
 
  Configure GPIO pins : USART_TX_Pin USART_RX_Pin
  GPIO_InitStruct.Pin = USART_TX_Pin|USART_RX_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF4_USART2;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
  Configure GPIO pin : LD2_Pin
  GPIO_InitStruct.Pin = LD2_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LD2_GPIO_Port, &GPIO_InitStruct);*/
 
  GPIO_InitStruct.Pin = GPIO_PIN_All;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
 
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);
 
  __HAL_RCC_GPIOC_CLK_DISABLE();
  __HAL_RCC_GPIOH_CLK_DISABLE();
  __HAL_RCC_GPIOA_CLK_DISABLE();
 
  HAL_NVIC_DisableIRQ(EXTI4_15_IRQn);
 
 
}
 
/* USER CODE BEGIN 4 */
 
/* USER CODE END 4 */
 
/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}
 
#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

Is there anything else i need to turn off to get my device to STOP Mode desired current of 0.8uA? Currently consuming 350uA

[Andrew Neil · Accepted solution]

Remember that this is not purely a software problem - you also have to pay attention to the hardware.

Have you been through the board's manual to ensure that everything else on the board is disabled?

Sometimes the manual misses a few details if you're chasing the absolute lowest drain - so you will also have to study the schematics in detail.

eg, see:

https://community.st.com/s/question/0D50X00009XkbSOSAZ/excess-current-consumption-running-bl072zlrwan1-from-battery

and:

https://community.st.com/s/question/0D50X00009q4M1zSAE/cant-power-bl072zlrwan1-with-battery

[JAvil.3]

Hi Andrew! Thank you for your input! I was able to bring down the power consumption to ~1.3nA. But this value is lower than my expectations for STOP Mode w/ RTC ( 0.86 µA Stop mode + RTC + 20-Kbyte RAM retention). Any advice for this?

[Andrew Neil]

Is it actually retaining the RAM and maintaining the RTC?

Are you sure you're measuring correctly?

[JAvil.3]

static void MX_RTC_Init(void)
{
 
  /* USER CODE BEGIN RTC_Init 0 */
 
  /* USER CODE END RTC_Init 0 */
 
  /* USER CODE BEGIN RTC_Init 1 */
 
  /* USER CODE END RTC_Init 1 */
 
  /** Initialize RTC Only
  */
  hrtc.Instance = RTC;
  hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
  hrtc.Init.AsynchPrediv = 127;
  hrtc.Init.SynchPrediv = 255;
  hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
  hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
  hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
  hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
  if (HAL_RTC_Init(&hrtc) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN RTC_Init 2 */
  HAL_RTCEx_DeactivateTimeStamp(&hrtc);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_1);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_2);
  HAL_RTCEx_DeactivateTamper(&hrtc, RTC_TAMPER_3);
  HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
  HAL_RTC_DeactivateAlarm(&hrtc, RTC_ALARM_A);
  HAL_RTC_DeactivateAlarm(&hrtc, RTC_ALARM_B);
  /* USER CODE END RTC_Init 2 */
 
}

I assume that this function generated by the STM32CubeID would initiate the RTC.

In regards to measuring, I have a DC Power Analyzer connected to IDD (JP6) of the board.

[Piranha]

Most likely 1,3 nA means there is something wrong with the measurement. For example, something else is supplying the MCU through the pin protection diodes.

Anyway, read this:

https://community.st.com/s/question/0D53W00001bnh8dSAA/how-to-enter-standby-or-shutdown-mode-on-stm32