Allegro launches coreless, Hall-effect current sensor for EVs and industrial applications

Allegro MicroSystems, Inc., a provider of sensing and power solutions for motion control and energy-efficient systems, has announced a new, coreless Hall-effect current sensor for demanding automotive and industrial systems. It offers higher accuracy and sensitivity, additional fault detection capabilities, and user programmability.

Allegro’s new ACS37610 sensor joins the ACS37612 as the industry’s first family of truly coreless Hall sensing solutions designed to measure currents from 100 A to greater than 4000 A flowing through a busbar or PCB trace with a typical 1 percent accuracy — with no need for an external concentrator or U-shaped magnetic shield.

These innovative solutions enable system designers to achieve enhanced efficiency and higher power density while reducing system complexity, BOM, cost, footprint, and weight.

“Allegro was first to market with coreless, differential Hall-effect current sensing technology, and our new ACS37610 IC enables our customers to accurately measure hundreds or thousands of amps in a very economical and simple way,” said Shaun Milano, director of Current Sensors at Allegro. “Our differential Hall-based sensors provide excellent immunity to stray magnetic fields without the need of a shield, required by competing solutions, that slows down response and adds non-linearity error into the system.”

Advanced features
The ACS37610 is an optimal choice for electric vehicle high-voltage traction motor inverters, 48V / 12V auxiliary inverters, heterogeneous redundant battery monitoring, overcurrent detection, smart fuses, power distribution units (PDUs), and power supplies.

The sensor’s 250 kHz bandwidth, dedicated overcurrent, an over-temperature fault pin, and a slew of built-in diagnostics make it ideal for safety-critical applications.

The ACS37610 features advanced differential sensing technology, resulting in a 2.5× improvement in signal-to-noise ratio (SNR) and a 2× lower noise relative to the ACS37612. The lower noise provides a higher-resolution required for accurate torque control, while the sensor’s 4× higher sensitivity range enables flexible busbar and PCB designs.

While not mandatory, a slight notch to the current-carrying busbar or PCB copper trace provides further improvements to the system’s SNR. The ACS37610 features larger Hall element spacing (2.5mm versus 1.8mm for the ACS37612) to accommodate wider notches, resulting in virtually no thermal performance degradation and no hotspots. The sensor can be mounted in a horizontal or vertical orientation relative to the busbar, providing superior flexibility in mechanical assemblies.

Design support
The ACS37610 current sensor is available now in a low-profile, lead (Pb)-free, 8-pin, surface-mount TSSOP package. The sensor’s ultra-compact package makes it ideal for space-constrained applications while enabling simple, cost-effective surface mount assembly.

To help developers accelerate their designs, Allegro offers evaluation kits and reference tools for current flowing through a PCB or busbar.