So most of the navigation devices come equipped with a magnetometer which can sense where the strongest magnetic field is coming from i.e. the magnetic north pole of earth and point towards it. The HMC5883 being a magnetometer sensor does the same thing, the sensor is also called GY271. This IC has 3 magneto-resistive materials inside which are arranged in the axes x, y and z. The amount of current flowing through these materials is sensitive to the earth’s magnetic field. So, changes in this current is measured and calculated to determine the directions. Care should be taken while using it as any strong magnetic material placed near it might force a false reading. This compass sensor module utilizes QMC5883L IC instead of HMC5883L because it is cheaper to manufacture and is most commonly available in the market. This is most commonly used as a Digital Compass Sensor or to detect any Ferrous (Magnetic) material. Additional Uses include Robotic Navigation and UAV Systems.
Specifications of Triple Axis Magnetometer Sensor Module
1.Input Voltage: +3V to +6V
2.QMC5883L IC
3.Range of -8 to +8 Gauss with 2 mGauss resolution
4.I2C interface
5.1-2 degree heading accuracy
6.Integrated 12-bit ADC
7.160Hz max data rate
Product Description
The module utilizes I2C communication protocol to communicate and has 5 pins on breakout board namely VCC, GND, SDA, SCL and DRDY. It has a voltage regulator on board so you van directly connect to the VCC pin from your Microcontroller Board and a 12-bit Analog to Digital Converter so that you can use any GPIO pin.
Additional Resources:
Datasheet of HMC5883L
HMC5883L Magnetometer Arduino Library
Arduino HMC5883L Interfacing