The MLX90393 is a micro power 3D Hall sensor which senses the magnetic field of the nearby magnet along the 3 perpendicular axes and gives these values, together with the chip temperature, on its digital (I2C or SPI) output. With these values the exact linear, rotary or 3D position of the magnet can be calculated by an external microcontroller.
With its 3x3mm footprint, the Melexis MLX90393 can fit in the tiniest of assemblies. The sensor is mostly characterized by the fact that it can interchange measurement speed for both current consumption and noise on the digital output signal, making it the flexible building block for any magnetic sensing application up to 85°C.
In single measurement mode, a bus master is requesting the sensor to perform a measurement, either by transmission of a command, or by issuing a trigger signal. Whenever the sensor is in burst mode, it wakes up and goes back to sleep at an in-application programmable duty cycle. Finally, the wake-up on change mode offers the same functionality as the burst mode, but only setting the interrupt pin high whenever the latest measurement differs more than a programmable threshold from either the previous measurement or the first measurement when entering the mode.
The sensor output data needs to be post-processed in order to calculate the angles or norms of the vector in order to get the desired position signal(s). This requires off-chip computation, and is a clear advantage in system-level partitioning by having one microcontroller interfacing with many sensors on the same bus.