目录
- 前言
- [1 原理图](#1 原理图)
- [2 IIC地址说明](#2 IIC地址说明)
- [3 寄存器地址说明](#3 寄存器地址说明)
- [4 开始工作前配置](#4 开始工作前配置)
- [5 程序代码](#5 程序代码)
前言
INA219 是一款具备 I2C 或 SMBUS 兼容接口的分流器和功率监测计。该器件监测分流器电压降和总线电源电压，转换次数和滤波选项可通过编程设定。可编程校准值与内部乘法器相结合，支持直接读取电流值（单位：安培）。通过附加乘法寄存器可计算功率（单位：瓦）。I2C 或 SMBUS 兼容接口 具有 16 个可编程地址。
INA219 可在 0V 至 26V 范围内感测总线中的分压。该器件由 3V 至 5.5V 单电源供电，电源的最大流耗为1mA。INA219 的工作温度范围为 -40°C 至 125°C。
1 原理图
2 IIC地址说明
此测试时A0、A1都下拉接地，所以INA219的IIC通信地址为1000000B
3 寄存器地址说明
- 0x00 配置寄存器，用来配置工作模式、采集范围以及其他参数
- 0x01 分流电阻两端的电压
- 0x02 总线电压（IN-到GND的电压差）
- 0x03 功率
- 0x04 经过分流电阻两端的电流
- 0x05 校准寄存器，用于对测量结果进行校准
4 开始工作前配置
- 0x00 寄存器Bit 13：设置检测最大检测电压 0 = 16V，1 = 32V （此处项目需要测3V到5V的电压，故设置Bit 13 为 0）
- 0x00 寄存器Bit 11-12：设置总线分流电阻最大的电压（此处项目需要测0A到5A的电流，故设置Bit 11-12 为 01，即量程±80mV，可测电流±8A）
- 0x00 寄存器Bit 0-2：设置工作模式（默认）
- 0x05 寄存器：设置基准值（根据需要测的电压、电流范围再套入公式得出结果）
由以下公式可得出0x05的配置值。
C a l = t r u n c ( 0.04096 C u r r e n t L S B × R s h u n t ) Cal = trunc\left ( \frac{0.04096}{CurrentLSB\times Rshunt} \right ) Cal=trunc(CurrentLSB×Rshunt0.04096)
C u r r e n t L S B = M a x i m u m E x p e c t e d C u r r e n t 2 15 CurrentLSB = \frac{Maximum Expected Current}{2^{15}} CurrentLSB=215MaximumExpectedCurrent
数据手册说明文档
5 程序代码
1）驱动程序
c
#include "main.h"
#include "ina219aidcnr_helper.h"
uint16_t ina219_calibrationValue;
uint16_t ina219_currentDivider_mA;
float ina219_powerMultiplier_mW;
/**
* @brief The IIC reads 16bit data from the specified register address.
* @param ina219 Slave configuration structure of the IIC.
* @param registerAddress Internal memory address.
* @return 16 bit register data.
*/
uint16_t INA219_ReadDataForRegister_16Bits(INA219_t *ina219, uint8_t registerAddress)
{
uint8_t Value[2];
HAL_I2C_Mem_Read(ina219->ina219_i2c, (INA219_ADDRESS<<1), registerAddress, 1, Value, 2, 1000);
return ((Value[0] << 8) | Value[1]);
}
/**
* @brief Writes 16 bits of data to the register.
* @param ina219 Slave configuration structure of the IIC.
* @param registerAddress Internal memory address.
* @param Value 16 bits of data to be written.
*/
void INA219_WriteDataToRegister_16Bits(INA219_t *ina219, uint8_t registerAddress, uint16_t Value)
{
uint8_t regAddr[2];
/* High Byte */
regAddr[0] = (Value >> 8) & 0xff;
/* Low Byte */
regAddr[1] = (Value >> 0) & 0xff;
HAL_I2C_Mem_Write(ina219->ina219_i2c, (INA219_ADDRESS<<1), registerAddress, 1, (uint8_t*)regAddr, 2, 1000);
}
/**
* @brief Read bus voltage.
* @param ina219 Slave configuration structure of the IIC.
* @return Read voltage value, unit mV.
*/
uint16_t INA219_ReadBusVoltage(INA219_t *ina219)
{
uint16_t result = INA219_ReadDataForRegister_16Bits(ina219, INA219_REG_BUS_VOLTAGE);
/* return mV */
return ((result >> 3 ) * 4);
}
/**
* @brief Read current register value.
* @param ina219 Slave configuration structure of the IIC.
* @return Current register value.
*/
uint16_t INA219_ReadCurrentRaw(INA219_t *ina219)
{
uint16_t result = INA219_ReadDataForRegister_16Bits(ina219, INA219_REG_CURRENT);
return (result);
}
/**
* @brief Read current register value, unit mA.
* @param ina219 Slave configuration structure of the IIC.
* @return Current value.
*/
uint16_t INA219_ReadCurrent_mA(INA219_t *ina219)
{
uint16_t result = INA219_ReadCurrentRaw(ina219);
return (result / ina219_currentDivider_mA);
}
/**
* @brief Read current register value, unit mV.
* @param ina219 Slave configuration structure of the IIC.
* @return Shunt Voltage value.
*/
uint16_t INA219_ReadShuntVoltage_mV(INA219_t *ina219)
{
uint16_t result = INA219_ReadDataForRegister_16Bits(ina219, INA219_REG_SHUNT_VOLTAGE);
/* When multiple sign bits are present, they will all be the same value.
* Negative numbers are represented in 2's complement format.
* Generate the 2's complement of a negative number by complementing the absolute value binary number and adding 1.
* Extend the sign, denoting a negative number by setting the MSB = 1.
* Extend the sign to any additional sign bits to form the 16-bit word. */
if(result > MAX_SHUNT_RANGE)
{
result = 65536 - MAX_SHUNT_RANGE;
}
/* Shunt voltage, unit mV. */
return (result / 100);
}
/**
* @brief INA219 system reset.
* @param ina219 Slave configuration structure of the IIC.
*/
void INA219_Reset(INA219_t *ina219)
{
INA219_WriteDataToRegister_16Bits(ina219, INA219_REG_CONFIG, INA219_CONFIG_RESET);
HAL_Delay(1);
}
/**
* @brief Set calibration register.
* @param ina219 Slave configuration structure of the IIC.
* @param calibrationData Calibrated data.
*/
void INA219_SetCalibration(INA219_t *ina219, uint16_t calibrationData)
{
INA219_WriteDataToRegister_16Bits(ina219, INA219_REG_CALIBRATION, calibrationData);
}
/**
* @brief Gets the value of the configuration register.
* @param ina219 Slave configuration structure of the IIC.
* @return Configuration Register value.
*/
uint16_t INA219_GetConfigInfo(INA219_t *ina219)
{
uint16_t result = INA219_ReadDataForRegister_16Bits(ina219, INA219_REG_CONFIG);
return result;
}
/**
* @brief Set configuration register.
* @param ina219 Slave configuration structure of the IIC.
* @param configData Configuration data.
*/
void INA219_SetConfig(INA219_t *ina219, uint16_t configData)
{
INA219_WriteDataToRegister_16Bits(ina219, INA219_REG_CONFIG, configData);
}
/**
* @brief The measurement results are calibrated. Voltage range is 16V, Current range is 8A.
* @param ina219 Slave configuration structure of the IIC.
*/
void INA219_SetCalibration_16V_8A(INA219_t *ina219)
{
uint16_t configInfo = INA219_CONFIG_VOLTAGE_RANGE_16V |
INA219_CONFIG_GAIN_2_80MV | INA219_CONFIG_BADCRES_12BIT |
INA219_CONFIG_SADCRES_12BIT_1S_532US |
INA219_CONFIG_MODE_SANDBVOLT_CONTINUOUS;
// Current_LSB = Maximum Expected Current / 2^15 = (80 / 10) / 2^15 = 0.0002
// Cal = 0.04096 / (Current_LSB / R) = 0.04096 / (0.0002A * 0.01R) = 20480 = 0x5000
// Calibration Register = 20480
ina219_calibrationValue = 20480;
// 1mA = Current_LSB * bits = 200uA * 5bit (5 bit/mA)
ina219_currentDivider_mA = 5;
// 1mW = Power_LSB * bits = 4mW * 0.25bit (0.25f bit/mW)
ina219_powerMultiplier_mW = 0.25f;
INA219_SetCalibration(ina219, ina219_calibrationValue);
INA219_SetConfig(ina219, configInfo);
}
/**
* @brief Ina219 driver initialization
* @param ina219 Slave configuration structure of the IIC.
* @param i2c Pointer to a I2C_HandleTypeDef structure that contains
* the configuration information for the specified I2C.
* @param Address Configuration data.
* @return status.
*/
uint8_t INA219_Init(INA219_t *ina219, I2C_HandleTypeDef *i2c, uint8_t Address)
{
ina219->ina219_i2c = i2c;
ina219->Address = Address;
ina219_currentDivider_mA = 0;
ina219_powerMultiplier_mW = 0;
uint8_t ina219_isReady = HAL_I2C_IsDeviceReady(i2c, (Address << 1), 3, 2);
if(ina219_isReady == HAL_OK)
{
INA219_Reset(ina219);
INA219_SetCalibration_16V_8A(ina219);
return 1;
}
else
{
return 0;
}
}2）头文件
c
#ifndef INA219AIDCNR_HELPER_H
#define INA219AIDCNR_HELPER_H
#define INA219_ADDRESS (0x40)
#define MAX_SHUNT_RANGE (0x0FA0)
/* Register */
#define INA219_REG_CONFIG (0x00)
#define INA219_REG_SHUNT_VOLTAGE (0x01)
#define INA219_REG_BUS_VOLTAGE (0x02)
#define INA219_REG_POWER (0x03)
#define INA219_REG_CURRENT (0x04)
#define INA219_REG_CALIBRATION (0x05)
//
#define INA219_CONFIG_RESET (0x8000)
//
#define INA219_CONFIG_VOLTAGE_RANGE_16V (0x0000) // 0-16V Range
#define INA219_CONFIG_VOLTAGE_RANGE_32V (0x2000) // 0-32V Range
#define INA219_CONFIG_GAIN_1_40MV (0x0000) // Gain 1, 40mV Range
#define INA219_CONFIG_GAIN_2_80MV (0x0800) // Gain 2, 80mV Range
#define NA219_CONFIG_GAIN_4_160MV (0x1000) // Gain 4, 160mV Range
#define INA219_CONFIG_GAIN_8_320MV (0x1800) // Gain 8, 320mV Range
#define INA219_CONFIG_BADCRES_9BIT (0x0000) // 9-bit bus res = 0..511
#define INA219_CONFIG_BADCRES_10BIT (0x0080) // 10-bit bus res = 0..1023
#define INA219_CONFIG_BADCRES_11BIT (0x0100) // 11-bit bus res = 0..2047
#define INA219_CONFIG_BADCRES_12BIT (0x0180) // 12-bit bus res = 0..4097
#define INA219_CONFIG_BADCRES_12BIT_2S_1060US (0x0480) // 2 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_4S_2130US (0x0500) // 4 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_8S_4260US (0x0580) // 8 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_16S_8510US (0x0600) // 16 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_32S_17MS (0x0680) // 32 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_64S_34MS (0x0700) // 64 x 12-bit bus samples averaged together
#define INA219_CONFIG_BADCRES_12BIT_128S_69MS (0x0780) // 128 x 12-bit bus samples averaged together
#define INA219_CONFIG_SADCRES_9BIT_1S_84US (0x0000) // 1 x 9-bit shunt sample
#define INA219_CONFIG_SADCRES_10BIT_1S_148US (0x0008) // 1 x 10-bit shunt sample
#define INA219_CONFIG_SADCRES_11BIT_1S_276US (0x0010) // 1 x 11-bit shunt sample
#define INA219_CONFIG_SADCRES_12BIT_1S_532US (0x0018) // 1 x 12-bit shunt sample
#define INA219_CONFIG_SADCRES_12BIT_2S_1060US (0x0048) // 2 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_4S_2130US (0x0050) // 4 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_8S_4260US (0x0058) // 8 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_16S_8510US (0x0060) // 16 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_32S_17MS (0x0068) // 32 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_64S_34MS (0x0070) // 64 x 12-bit shunt samples averaged together
#define INA219_CONFIG_SADCRES_12BIT_128S_69MS (0x0078) // 128 x 12-bit shunt samples averaged together
#define INA219_CONFIG_MODE_MASK 0x07
#define INA219_CONFIG_MODE_POWERDOWN 0x00
#define INA219_CONFIG_MODE_SVOLT_TRIGGERED 0x01
#define INA219_CONFIG_MODE_BVOLT_TRIGGERED 0x02
#define INA219_CONFIG_MODE_SANDBVOLT_TRIGGERED 0x03
#define INA219_CONFIG_MODE_ADCOFF 0x04
#define INA219_CONFIG_MODE_SVOLT_CONTINUOUS 0x05
#define INA219_CONFIG_MODE_BVOLT_CONTINUOUS 0x06
#define INA219_CONFIG_MODE_SANDBVOLT_CONTINUOUS 0x07
typedef struct
{
I2C_HandleTypeDef *ina219_i2c;
uint8_t Address;
} INA219_t;
uint8_t INA219_Init(INA219_t *ina219, I2C_HandleTypeDef *i2c, uint8_t Address);
uint16_t INA219_ReadBusVoltage(INA219_t *ina219);
uint16_t INA219_ReadCurrent_mA(INA219_t *ina219);
uint16_t INA219_ReadCurrent_raw(INA219_t *ina219);
uint16_t INA219_ReadShuntVoltage_mV(INA219_t *ina219);
uint16_t INA219_ReadDataForRegister_16Bits(INA219_t *ina219, uint8_t registerAddress);
uint16_t INA219_GetConfigInfo(INA219_t *ina219);
void INA219_Reset(INA219_t *ina219);
void INA219_SetCalibration(INA219_t *ina219, uint16_t calibrationData);
void INA219_SetConfig(INA219_t *ina219, uint16_t configData);
void INA219_SetCalibration_16V_8A(INA219_t *ina219);
void INA219_WriteDataToRegister_16Bits(INA219_t *ina219, uint8_t registerAddress, uint16_t Value);
#endif //INA219AIDCNR_HELPER_H3) 测试代码
c
int main(void)
{
/* USER CODE BEGIN 1 */
uint16_t vbus, vshunt, current;
/* 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_USART1_UART_Init();
MX_I2C2_Init();
/* USER CODE BEGIN 2 */
while(!INA219_Init(&ina219, &hi2c2, INA219_ADDRESS))
{
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
vbus = INA219_ReadBusVoltage(&ina219);
vshunt = INA219_ReadShuntVoltage_mV(&ina219);
current = INA219_ReadCurrent_mA(&ina219);
sprintf(strBuffer, "INA219 param: vbus:%d mV; current:%d mA\r\n", vbus, current);
HAL_UART_Transmit(&huart1, strBuffer, strlen(strDataBuf), 0xff);
UserDelay_ms(500);
}