How to Use Adafruit INA228: Examples, Pinouts, and Specs

The Adafruit INA228 is a high-precision, low-drift current sensor capable of measuring current, voltage, and power. It is designed for applications requiring accurate power monitoring and energy metering. This versatile sensor is ideal for use in battery-operated devices, power management systems, and energy monitoring applications.

1. Power Supply: Connect the VCC pin to a 2.7V to 5.5V power supply and the GND pin to the ground.
2. I2C Communication: Connect the SCL and SDA pins to the corresponding I2C lines on your microcontroller.
3. Current Measurement: Connect the IN+ and IN- pins in series with the load you want to measure.
4. Address Selection: Use the ADDR pin to set the I2C address. This can be done by connecting it to VCC, GND, or leaving it floating.
5. Alert Output: The ALERT pin can be used to trigger an interrupt on your microcontroller when a certain condition is met (e.g., overcurrent).

• Bypass Capacitor: Place a 0.1µF bypass capacitor close to the VCC pin to filter out noise.
• Shunt Resistor: Use a precise shunt resistor for accurate current measurements.
• I2C Pull-up Resistors: Ensure that the I2C lines have appropriate pull-up resistors (typically 4.7kΩ).
• Thermal Management: Ensure proper thermal management to avoid overheating, especially in high-current applications.

Below is an example code to interface the Adafruit INA228 with an Arduino UNO using the I2C protocol.

#include <Wire.h>
#include <Adafruit_INA228.h>

// Create an instance of the INA228 class
Adafruit_INA228 ina228;

void setup() {
  Serial.begin(9600);
  // Initialize I2C communication
  Wire.begin();
  
  // Initialize the INA228 sensor
  if (!ina228.begin()) {
    Serial.println("Failed to find INA228 chip");
    while (1) { delay(10); }
  }
  Serial.println("INA228 Found!");
}

void loop() {
  // Read current, voltage, and power
  float current = ina228.readCurrent();
  float voltage = ina228.readBusVoltage();
  float power = ina228.readPower();
  
  // Print the values to the Serial Monitor
  Serial.print("Current: "); Serial.print(current); Serial.println(" A");
  Serial.print("Voltage: "); Serial.print(voltage); Serial.println(" V");
  Serial.print("Power: "); Serial.print(power); Serial.println(" W");
  
  delay(1000); // Wait for 1 second before the next reading
}

1. No Communication with the Sensor:

   • Solution: Check the I2C connections and ensure the correct I2C address is used. Verify that the pull-up resistors are in place.

2. Incorrect Readings:

   • Solution: Ensure that the shunt resistor is of the correct value and precision. Verify that the connections are secure and there is no noise interference.

3. Overheating:

   • Solution: Ensure proper thermal management and avoid exceeding the maximum current rating.

• Check Connections: Ensure all connections are secure and correctly placed.
• Verify Power Supply: Ensure the power supply voltage is within the specified range.
• Use Proper Pull-up Resistors: Ensure the I2C lines have appropriate pull-up resistors.
• Consult the Datasheet: Refer to the Adafruit INA228 datasheet for detailed information and advanced configurations.

By following this documentation, users can effectively integrate the Adafruit INA228 into their projects, ensuring accurate and reliable current, voltage, and power measurements.