ASIL-compliant sensors target EV current monitoring
Two sensor products from Melexis, the MLX91230 and the MLX91231, offer access to shunt or Hall type current sensor technologies. These ASIL-compliant devices can measure voltage, current and temperature.
The MLX91230 is a conventional Hall sensor and is complemented by the MLX91231 shunt interface current sensor IC. They target high voltage battery functions, such as current monitoring in battery management system, battery disconnect units (also known as battery junction boxes) and power relay assemblies.
The MLX91230 exhibits less than one per cent sensitivity drift and 100mA offset over temperature and operational lifespan. The MLX91231 has a sub-0.5 per cent sensitivity drift with a 50mA offset.
A single product family offering both shunt and Hall-based current sensing allows Tier 1 companies to decide which combination is the best fit for each vehicle OEM. They can easily switch from one configuration to the other if requirements change, said Melexis. OEMs can integrate different combinations into vehicle models and reusability minimises the engineering effort.
Designed according to the ISO 26262 functional safety standard, both current sensor devices offer full support for ASIL integration. The MLX91230 is naturally isolated, while the MLX91231 needs external isolation. Each sensor has an integrated temperature sensor as well as a dedicated safety rated over-current detection pin. They are housed in compact eight-pin SOIC packages.
“The new MLX91230/MLX91231 current sensor family is meeting our customers’ demands for a versatile modular BMS [battery management system] development strategy. It allows them to achieve much more with less engineering resources,” said Bruno Boury, product line manager at Melexis.
Testing samples (B-sample) and evaluation kits are available on demand. The MLX91230 Hall-based current sensor will be released in Q2 2023, with the MLX91231 shunt device following soon after.
Melexis designs, develops and delivers micro-electronic products and mixed-signal semiconductor sensors and actuators to integrate sensing, driving and communication into products and systems.
The company says it is a world leader in automotive sensors – on average, every new car produced worldwide contains 18 Melexis chips. The company also serves the alternative mobility, smart appliances, smart buildings, robotics, energy management and digital health markets.
Melexis is headquartered in Belgium.
