Integrated Current Sensors Expand Automotive Power Measurement

The MLX91224 and MLX91225 integrate the current conductor, sensing element, signal conditioning, and galvanic isolation within a compact surface-mount package. Current passes directly through the low-impedance lead frame, generating a magnetic field that is differentially measured by two sets of Hall plates. This dual-plate configuration minimizes susceptibility to external stray magnetic fields while producing a high-speed linear analog output. Package-dependent isolation structures provide working voltages up to 1640 VRMS, eliminating the external isolation amplifiers and complex assembly steps typically required by conventional shunt-based measurement alternatives.

Functional Safety and Packaging Options
Developed as ISO 26262 Safety Elements out of Context, the platform achieves ASIL B readiness for high-voltage automotive architectures. The devices are delivered in three package variants to accommodate specific thermal, electrical, and surge requirements. The SOIC6FL DE package supports continuous operating currents up to 50 A with integrated overcurrent detection. The SOIC16W DG variant maintains a comparable current range while increasing creepage and clearance distances for higher insulation demands. For demanding high-power systems, the SOIC12W FL DH package extends continuous operation up to 100 ARMS alongside surge-current ratings reaching plus or minus 29 kA.

Operational Parameters and System Integration
The sensor platform accommodates both alternating current and direct current measurements, supporting bipolar and unipolar sensing alongside ratiometric or fixed output configurations. The MLX91224 operates within 5-volt architectures, whereas the MLX91225 interfaces with 3.3-volt microcontroller supply rails. Overcurrent detection functions via a dedicated pin with internally or externally configured thresholds. Operating across a temperature range from -40 °C to 150 °C, the components target automotive motor control, DC-DC converters, photovoltaic inverters, and server power distribution units.

Additional Context:
This section details technical specifications and competitive benchmarking not included in the original product announcement

The MLX91224 and MLX91225 position themselves within the high-voltage integrated Hall-effect current sensor segment for currents up to 100 ARMS. Compared directly to conventional shunt resistors, this integrated solution eliminates ohmic power losses along the measurement path as well as the requirement for external isolation amplifiers. Relative to open-loop magnetic core current transducers, the SOIC package variants from Melexis offer a significantly reduced physical footprint and integrated functional safety features compliant with ISO 26262 (ASIL B). Competing monolithic current sensors in comparable power classes often utilize alternative semiconductor technologies but frequently necessitate external end-of-line calibration and adjustment steps, which are bypassed by this platform's factory signal conditioning.

Edited by Sucithra Mani, Induportals editor – adapted by AI.

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