FTM / Intelligent Lighting / Melexis — MLX90394 Magnetometer

Melexis — MLX90394 Magnetometer

June 20, 2024
Intelligent Lighting, Intelligent Sensing
Issue 3 2024, Issue 5 2024

Tiny 3D magnetometer gives superior performance and high reliability

The new MLX90394 magnetometer from Melexis achieves an excellent trade-off between low noise, power consumption and cost to give designers an effective way to build position-sensing functions into an end product.

Melexis has introduced the MLX90394 Triaxis® micropower magnetometer, a tiny Hall-effect based sensor which balances the design trade-off between low noise, power consumption, and cost. It is suitable for rotary and linear sensing systems, push-buttons, and 3D joystick control in gaming and industrial peripherals.

Offering selectable modes and broad configurability, the MLX90394 enables OEMs to reuse a single hardware design across multiple product variants, and to reduce time-to-market. Helping to save power, the modes can be selected on-the-fly.

In position sensing functions, the MLX90394 provides an elegant, flexible and reliable alternative to traditional potentiometers, which suffer from contamination of the wiper surface as well as packaging constraints. The contactless MLX90394 is also more reliable than contacting switches.

Supplied in a compact 2 mm x 1.5 mm x 0.4 mm six-lead UTDFN package, this magnetometer helps designers to implement smaller, slicker human-machine interfaces.

The MLX90394 architecture delivers several benefits compared to existing solutions. It enables measurement and output of each magnetic axis individually. A built-in thermometer allows selectable temperature measurement to enable compensation for measurement error.

Features

16-bit digital I2C output for magnetic and temperature data
Output data rate options: 0.1 MHz, 0.4 MHz and 1 MHz
Three wake-up-on-change/interrupt modes
Measurement-range options:
- ±5 mT (0.15μT/LSB)
- ±50 mT (1.5μT/LSB)
Operating-temperature range: -40°C to 105°C
Supply-voltage range: 1.7 V to 3.6 V

Applications

PC peripherals
Mouse roller
Gaming peripherals:
- Joysticks
- D-pads
- Trigger buttons
Wearable devices
Battery powered tools
White goods
Industrial peripherals
Smart home devices
Door/window opening detectors

Evaluation Board/Development Kit

Part Number: EVB90394_DVK_000, EVB90394_DVK_001 (DVK magnetic versions)

The EVB90394 evaluation board from Melexis provides an easy way to connect the MLX90394 Triaxis® magnetometer IC to a microcontroller or measurement device.

The MLX90394 IC is mounted on the EVB90394 together with a 100 nF decoupling capacitor and three pull-up resistors. Two precision headers are available for compatibility with the Melexis Triaxis DVKMagnetic board, which is supplied separately.

The DVKMagnetic kit provides an easy way to connect the EVB90394 to magnetic devices such as a rotary knob, linear slider and joystick, which are included in the kit along with an off-axis magnet holder. The interface also provides pin-outs for an external LCD display and Arduino/Mbed boards, which are not included.