3 Axis Magnetometer
There are just few things to say about this device. It returns on I2C bus the values for the X, Y, Z magnetic field vectors. Integrating this values with an accelerometers, in order to measure the tilt, we have a tilt compensated compass, that measures the correct north bearing even if the rover is skewed.
The schematic diagram is very simple, everything is inside the chip. Being highly integrated, the datasheet
is not simple as well.
This sensors combination is the electronic equivalent of the nautical compasses, widely used once, where gimbals compensate the tilt of the ship on maintaining the compass in a horizontal asset.