High-accuracy current sensors optimised for affordable e-mobility

Melexis offers the MLX91211 Hall-effect current-sensing IC. Two variants are provided, offering a selection of features and performance to satisfy cost-sensitive applications. These range from belt-driven starter generators to traction inverters for low-speed EVs and e-scooters, as well as industrial applications including electrified forklift trucks and pallet trucks.

Combined with a ferromagnetic core, these non-intrusive sensors generate an analog output proportionate to the current flowing in the cable or bus bar. The output signal has a 40kHz bandwidth, and the sensor offers a step response time below 10µs.

The MLX91211LUA-ABT is factory-calibrated at three temperature points, facilitating increased accuracy for motor control in more challenging use cases. The lowest-priced version, the MLX91211LUA-ABA, addresses applications that have lower bandwidth and lower accuracy needs.

“These proven hybrid and electric-drive architectures are being adopted in affordable e-mobility traction solutions such as two-wheel and three-wheel e-bikes, e-scooters and low-speed electric vehicles, as well as 12V/48V starter generator applications on entry-level passenger cars,” explained Bruno Boury, product line manager, Current sensors, at Melexis. “Our MLX91211 sensor ICs now let designers create competitively priced modules by combining the high accuracy (sensitivity thermal drift better than 1.5%) needed for a great driving experience with features tailored for economy and reliability. To date, ferromagnetic concentrator technology remains the most reliable and proven contactless current sensing technology.”

Both devices are qualified to AEC-Q100 Grade 0, covering ambient temperatures from -40C to 150C for usage in all automotive environments, including under the hood.