Low-voltage 3D Magnetometer with Triaxis Hall Magnetic-Sensing Technology for Smart Metering and Consumer Applications

Published  May 7, 2021   0
MLX90392 3D Magnetometer from Melexis

The compact, low-voltage 3D magnetometer, MLX90392 from Melexis with Triaxis Hall magnetic-sensing technology, operates from a 1.8 V power rail shared with other components such as logic devices. Suitable for cost-conscious white goods, smart metering, gaming, home security, and other consumer applications, this three-axis magnetic field sensor eliminates the need for dedicated LDO or regulator, simplifies design, trims bill-of-materials costs, and saves PCB space. 

Measuring 2 mm x 2.5 mm x 0.4 mm, the MLX90392 sensor features a UTDFN-8 ultra-thin no-lead 8-pin package. This helps designers to tackle space-constrained applications. Besides, the 1.5 µA power-down mode helps save energy and maximizes runtime in battery-powered applications.

The integrated thermal sensor and I2C communication protocol feature place 16-bit position measurements in X, Y, Z axes, and temperature onto the I2C bus operating at up to 1 MHz. In all, there are two variants available enabling consumers to choose from ±50 mT and ±5 mT full-scale range, leveraging Melexis’ patented Triaxis Hall technology to deliver low noise and best-in-class accuracy.

The ±50 mT range is optimal for position measurement in HMI applications, door-closure detection in white goods and access-control systems, anti-tamper for smart meters, and contactless joysticks that save the power dissipated by the traditional position sensing with potentiometers. The ±5 mT variant has a sensitivity of 0.15 µT/LSB and typical RMS noise down to 0.3 µT, which is apt for position sensing that requires a small magnetic range and for precise position measurement where noise is a critical design parameter. Both the ±50 mT and ±5 mT devices support single-measurement and continuous-measurement modes, giving outstanding design flexibility, while self-test status, data-ready, and magnetic sensor-overflow indication provide comprehensive diagnostics.