【实验硬件】
1、ST NUCLEO-U5A5ZJ-Q开发板
2、数字电源
3、两个万用表
【开发软件】
1、stm32CubeMAX
2、Keil5.38
【实验步骤】
1、阅读资料《RM0456》在第38.3.3中给出了我们两个放大器的输入与输出的管脚。
在下表中列出了PAG模式的原理图,可以选择放大为2,4,8,16倍的增益输出。
2、明白了原理后,打开stm32cubeMAX配置opamp1:
【代码添加】
1、在代码中,自动给出了生成代码的初始化,但是如果要使用OPAMP还需要添加 HAL_OPAMP_Start(&hopamp1);这一句才能启动,当然如果在低功耗的场景,我们也可以使用HAL_OPAMP_Stop(&hopamp1);来停止放大器的工作。
具体代码如下:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* [url=home.php?mod=space&uid=1307177]@File[/url] GPIO/GPIO_IOToggle/Src/main.c
* [url=home.php?mod=space&uid=1315547]@author[/url] MCD Application Team
* [url=home.php?mod=space&uid=159083]@brief[/url] This example describes how to configure and use GPIOs through
* the STM32U5xx HAL API.
******************************************************************************
* [url=home.php?mod=space&uid=1020061]@attention[/url] *
* Copyright (c) 2022 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "icache.h"
#include "memorymap.h"
#include "opamp.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "tos_k.h "
#include "cmsis_os.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
extern OPAMP_HandleTypeDef hopamp1;
/* 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 ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
static GPIO_InitTypeDef GPIO_InitStruct;
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void SystemPower_Config(void);
/* USER CODE BEGIN PFP */
//task1
#define TASK1_STK_SIZE 512
void task1(void *pdata);
osThreadDef(task1, osPriorityNormal, 1, TASK1_STK_SIZE);
//task2
#define TASK2_STK_SIZE 512
void task2(void *pdata);
osThreadDef(task2, osPriorityNormal, 1, TASK2_STK_SIZE);
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void task1(void *pdata)
{
while(1)
{
HAL_GPIO_TogglePin(LED1_GPIO_PORT, LED1_PIN);
osDelay(200);
}
}
void task2(void *pdata) {
while(1) {
HAL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);
osDelay(1000);
}
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* STM32U5xx HAL library initialization:
- Configure the Flash prefetch
- Configure the Systick to generate an interrupt each 1 msec
- Set NVIC Group Priority to 3
- Low Level Initialization
*/
/* 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();
/* Configure the System Power */
SystemPower_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_ICACHE_Init();
MX_USART1_UART_Init();
MX_USART2_UART_Init();
MX_OPAMP1_Init();
/* USER CODE BEGIN 2 */
HAL_OPAMP_Start(&hopamp1);
/* -1- Enable GPIO Clock (to be able to program the configuration registers) */
LED1_GPIO_CLK_ENABLE();
LED2_GPIO_CLK_ENABLE();
/* -2- Configure IO in output push-pull mode to drive external LEDs */
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Pin = LED1_PIN;
HAL_GPIO_Init(LED1_GPIO_PORT, &GPIO_InitStruct);
GPIO_InitStruct.Pin = LED2_PIN;
HAL_GPIO_Init(LED2_GPIO_PORT, &GPIO_InitStruct);
osKernelInitialize();
osThreadCreate(osThread(task1),NULL);
osThreadCreate(osThread(task2),NULL);
osKernelStart();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
HAL_GPIO_TogglePin(LED1_GPIO_PORT, LED1_PIN);
/* Insert delay 100 ms */
HAL_Delay(100);
HAL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);
/* Insert delay 100 ms */
HAL_Delay(100);
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_ON;
RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_4;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI;
RCC_OscInitStruct.PLL.PLLMBOOST = RCC_PLLMBOOST_DIV1;
RCC_OscInitStruct.PLL.PLLM = 1;
RCC_OscInitStruct.PLL.PLLN = 80;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLLVCIRANGE_0;
RCC_OscInitStruct.PLL.PLLFRACN = 0;
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_CLOCKTYPE_PCLK3;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
{
Error_Handler();
}
}
/**
* @brief Power Configuration
* @retval None
*/
static void SystemPower_Config(void)
{
/*
* Disable the internal Pull-Up in Dead Battery pins of UCPD peripheral
*/
HAL_PWREx_DisableUCPDDeadBattery();
/*
* Switch to SMPS regulator instead of LDO
*/
if (HAL_PWREx_ConfigSupply(PWR_SMPS_SUPPLY) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN PWR */
/* USER CODE END PWR */
}
/* 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 */
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) */
/* Infinite loop */
while (1)
{
}
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
【实验效果】
在2倍增益的效果下
输入电压(mv) | 输出电压(mv) | 差值(mv) |
8.3 | 17.8 | -.1.2 |
18.2 | 37.6 | -1.2 |
98.2 | 197.8 | -1.4 |
198.1 | 389.2 | 7 |
495 | 998.5 | -8.5 |
993 | 1999.3 | -13.3 |
1492 | 3002.3 | -18.3 |
1592 | 3203 | -19 |
注差值为:V输入*2-V输出
【总结】
经过上述的测试,在输入电压不变的情况下,输出也非常稳定,误差也控制得非常不错。
引用: 秦天qintian0303 发表于 2024-2-14 23:22 列出了PAG模式的原理图,可以选择放大为2,4,8,16倍的增益输出,可以直接固定增益的还是挺方便的
对呀,还可以通过放大后接入ADC进行测量,挺方便的。
引用: lugl4313820 发表于 2024-2-15 10:48 对呀,还可以通过放大后接入ADC进行测量,挺方便的。
这就省的自己配置,而且这种内置的一般干扰应该会少一点
高级,这个OPAMP用处应该非常大,学习了。
引用: HonestQiao 发表于 2024-2-18 17:59 高级,这个OPAMP用处应该非常大,学习了。
感谢帮主的关注,我还是刚接触这OPAMP,希望帮主大佬多多指点!