STM32L152的低功耗测试

本文将验证STM32L32在stop模式下的低功耗电流。

在ST官网的STM32L152RE芯片介绍上明确有说明此芯片在stop模式下可以达到560nA，纳安！并且还可以支持16个外部中断唤醒。

真的这么强！下面来验证一下。

采用NUCLEO-L152板子进行验证，使用CubeMx生成工程代码。

在CubeMx中选择STM32L152RE这款芯片，pinout如下设置：

如上图，只是简单地将PC13,PB9,PB5,PB4,PD2,PA12,PB15,PB1设置为外部中断。

为了得到最低功耗，时钟树采用芯片内部时钟HSI：

在configuration下，将GPIO都设置为下拉，PC13在NUCLEO板子上是按键，设为上拉。

生成代码。main函数稍作修改：

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();

  /* Configure the system clock */
  SystemClock_Config();

  /* Initialize all configured peripherals */
  MX_GPIO_Init();

  /* USER CODE BEGIN 2 */
  HAL_PWREx_EnableUltraLowPower();
  HAL_PWREx_EnableFastWakeUp();
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
  /* USER CODE END WHILE */

  /* USER CODE BEGIN 3 */
	HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);

    /* Configures system clock after wake-up from STOP: enable HSI, PLL and select
      PLL as system clock source (HSI and PLL are disabled automatically in STOP mode) */
    SystemClockConfig_STOP();
    HAL_Delay(200);
  }
  /* USER CODE END 3 */

}

SystemClockConfig_STOP函数如下配置：

static void SystemClockConfig_STOP(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};

  /* Enable Power Control clock */
  __HAL_RCC_PWR_CLK_ENABLE();

  /* The voltage scaling allows optimizing the power consumption when the device is
     clocked below the maximum system frequency, to update the voltage scaling value
     regarding system frequency refer to product datasheet.  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  /* Poll VOSF bit of in PWR_CSR. Wait until it is reset to 0 */
  while (__HAL_PWR_GET_FLAG(PWR_FLAG_VOS) != RESET) {};

  /* Get the Oscillators configuration according to the internal RCC registers */
  HAL_RCC_GetOscConfig(&RCC_OscInitStruct);

  /* After wake-up from STOP reconfigure the system clock: Enable HSI and PLL */
  RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSEState            = RCC_HSE_OFF;
  RCC_OscInitStruct.HSIState            = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource       = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLMUL          = RCC_PLL_MUL6;
  RCC_OscInitStruct.PLL.PLLDIV          = RCC_PLL_DIV3;
  if(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2
     clocks dividers */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  if(HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
  {
    Error_Handler();
  }
}

编译烧录后使用电流表进行测试：

0.3uA! 看来所言非虚，300nA,按下按键，发现电流变大了，如下：

电流变为11mA，这个位为工作电流，这说明外部中断生效了。

STM32L152在低功耗这块，确实还不错！实测stop模式下300nA的电流，比手册上所示的560nA还低，看来ST还是比较保守。