Arduino driver for the MLX90393 3-axis magnetometer sensor.

The MLX90393 is a high-performance magnetic field sensor with an I²C interface, capable of measuring magnetic field strength in X, Y, and Z axes. It is suitable for applications like compasses, position sensing, and industrial measurements.

This library provides a simple interface for configuring the sensor and reading magnetic field values in microtesla (µT).

• 3-axis magnetic field measurement (X, Y, Z)
• Raw data reading
• Configurable gain
• Resolution control (16–19 bit)
• Oversampling (OSR) configuration
• Digital filter configuration
• Offset calibration support
• Register-level access (advanced users)
• ESP32 custom I²C pin support

• Arduino UNO / Mega
• ESP32
• Any board supporting the Wire (I²C) library

Supported sensor:

7Semi 3-Axis Magnetometer I2C Breakout - MLX90393

The MLX90393 communicates using I²C.

Default sensor address:

0x0C

Recommended I²C speed:

100 kHz – 400 kHz

1. Open Arduino IDE
2. Go to Library Manager
3. Search for 7Semi MLX90393
4. Click Install

1. Download this repository as ZIP
2. Arduino IDE → Sketch → Include Library → Add .ZIP Library

#include <7Semi_MLX90393.h>

MLX90393_7Semi mag;

void setup()
{
  Serial.begin(115200);

  if(!mag.begin())
  {
    Serial.println("MLX90393 not detected");
    while(1);
  }
}

void loop()
{
  float x, y, z;

  if(mag.readMag(x, y, z))
  {
    Serial.print("X: ");
    Serial.print(x);
    Serial.print(" Y: ");
    Serial.print(y);
    Serial.print(" Z: ");
    Serial.println(z);
  }

  delay(500);
}

float x, y, z;

mag.readMag(x, y, z);

Serial.print("X: ");
Serial.print(x);
Serial.print(" Y: ");
Serial.print(y);
Serial.print(" Z: ");
Serial.println(z);

Returns magnetic field values in microtesla (µT).

int16_t x, y, z;

mag.readMagRaw(x, y, z);

Serial.print("Raw X: ");
Serial.println(x);

Returns raw ADC values.

mag.setGain(MLX90393_GAIN_0_751);

Available gain settings:

MLX90393_GAIN_0_751
MLX90393_GAIN_0_601
MLX90393_GAIN_0_451
MLX90393_GAIN_0_376
MLX90393_GAIN_0_300
MLX90393_GAIN_0_250
MLX90393_GAIN_0_200
MLX90393_GAIN_0_150

mag.setResolution(
  MLX90393_RES_19BIT,
  MLX90393_RES_19BIT,
  MLX90393_RES_19BIT);

Resolution options:

MLX90393_RES_16BIT
MLX90393_RES_17BIT
MLX90393_RES_18BIT
MLX90393_RES_19BIT

Higher resolution increases precision but reduces speed.

mag.setOSR(MLX90393_OSR_3);

Available OSR settings:

MLX90393_OSR_0
MLX90393_OSR_1
MLX90393_OSR_2
MLX90393_OSR_3

Higher OSR improves accuracy but slows down measurements.

mag.setFilter(MLX90393_FILTER_7);

Available filter settings:

MLX90393_FILTER_0 to MLX90393_FILTER_7

Higher filter values provide smoother readings.

mag.setOffset(10, -5, 3);

Used for zero-field calibration.

Typical applications include:

• Digital compass
• Position sensing
• Magnetic field detection
• Industrial monitoring
• Robotics orientation
• Automotive sensing

MIT License

7Semi