21 May 2024

Safety rated field current sensor

Allegro ACS37601

Allegro MicroSystems has announced the release of samples for the ACS37601, an ASIL C safety rated, high-precision, field current sensor with best-in-class accuracy for traction and auxiliary inverter systems as well as battery management systems (BMS) in electric vehicles (EVs).

Designers of inverter and battery management systems are challenged to achieve higher safety targets based on new Automotive Safety Integrity Level (ASIL) requirements. To enable customers to meet these new safety requirements, while increasing system efficiency and extending battery life, Allegro has developed the ACS37601 programmable linear Hall-effect current sensor IC with overcurrent, overtemperature, and self-test capabilities. Designed to achieve high accuracy and resolution without compromising bandwidth, the ACS37601 is Allegro’s highest-accuracy field current sensor for applications requiring measurement capability greater than 200 Amperes.

“Allegro’s ACS37601 is enabling us to meet e-mobility functional safety and accuracy requirements in our BMS and EV traction inverter current sensor applications,” says Julio Urrea, Vice President of Business Development at Littelfuse, a diversified industrial technology company empowering a sustainable, connected, and safer world in the electronics, transportation, and industrial markets.

To be used along with a C-core, the ACS37601 is the first ASIL C-rated field current sensor that achieves 0.8% sensitivity error and less than 5 mV offset error over the automotive temperature range, and—with 30% less noise than legacy devices—this IC is ideal for battery management applications. The high operating bandwidth from DC to 240 kHz and fast 2 μs response time enable new performance in DC battery charging and high-frequency automotive inverter applications. To support adoption of the most advanced microprocessors without requiring additional components, the ACS37601 works with 5 V or 3.3 V power supplies.

“Littelfuse has a history of excellence as an automotive supplier with a tremendous global footprint. We are excited to work with them to deliver industry-leading magnetic current sensor accuracy and safety to EV powertrain applications,” says Shaun Milano, Business Unit Director for Current Sensors at Allegro.

To help designers deliver the most-advanced ASIL-compliant battery management and inverter systems, samples of the ACS37601 are currently offered in an extremely thin (1 mm-thick), 4-pin single in-line package (SIP), referred to as the KT package. The KT package is available in straight leads (suffix TN) as well as a lead-formed option (suffix TH), enabling surface-mount assembly and a high tolerance to mechanical vibrations. The package is lead (Pb) free, with 100% matt tin leadframe plating.

Company info: Allegro Microsystems