At Sensors Expo 2018, Vinicius (Vinnie) Cardoso, a field application engineer at Melexis, demonstrates the capabilities of the company’s magnetic position sensors. Using an extremely eye catching 3-D LED structure, he shows how the MLX90333 Triaxis® position sensor indicates the position of a magnet.
With red and blue LEDs indicating the north-south poles of a magnet, rotating the display knob identifies the location of the magnet. Pushing or pulling the shaft of the knob, the magnet passes through an analog digital threshold that indicates the intensity or magnitude of the field.
The MLX90333 has single output (rotary/linear) and dual outputs (3D/joystick) (3D-Magnetometer) modes with 12-bit angular resolution and 10-bit angular accuracy. The AEC-Q100 qualified (grade 0) sensor has a -40°C – +150°C ambient temperature range.
For the recently introduced Triaxis Gen III products MLX90371 and MLX90372 with stray field immunity, the reading is not affected by the presence of magnetic fields near the sensor. Stray field immunity is especially important in automotive applications with high current loads such as electric vehicles. The design uses a four-pole ring magnet to provide the stray field immunity.
Using an integrated magnetic concentrator (IMC) on its surface, the monolithic device senses three spatial components. Both new sensors have a Triaxis Hall magnetic front end, an analog to digital signal conditioner, a DSP for advanced signal processing and an output stage driver.In contrast to the MLX90371 that has an analog or PWM output, the MLX90372 offers SENT (SAE J2716, rev Apr 2016) or PWM output.