Bidirectional 200-A Hall Current Sensor Debuts 1,400-V Isolation

What you’ll learn:

• How the ACS37200’s 50-µΩ integrated conductor cuts sensing losses by up to 90% compared to a 0.5-mΩ shunt in 100-A designs, improving thermal headroom and system efficiency.
• How Allegro’s Hall-based current sensor architecture and experience from devices such as the ACS37002 enable tight accuracy, fast response, and robust isolation in compact high power layouts.

Allegro MicroSystems’ ACS37200 is a ±200-A galvanically isolated Hall-effect current sensor that targets the power dissipation problems created by traditional high-current shunt solutions in HEV and EV powertrains, industrial drives, and AI data center supplies. Claimed to have an industry-leading 50-µΩ primary conductor, the device cuts sensing-related power loss by about 90% relative to a typical 0.5-mΩ shunt at 100 A, reducing dissipation from roughly 5 W to 0.5 W.

This reduction in I²R loss directly improves power density. A compact 100-mm² PSOF package (see figure) and integrated 1,400-V isolation allows the ACS37200 to achieve a significantly smaller footprint than discrete shunts with isolation amplifiers. It also eliminates bulky heatsinks that are often required to manage shunt self-heating.

Allegro said that the overall footprint is around 20X smaller than a traditional discrete implementation, which creates valuable board area in traction inverters, solar inverters and rack power shelves.

The ACS37200 builds on Allegro’s established Hall sensor portfolio, which includes devices such as the ACS37002 that combines an integrated primary conductor with a precision Hall front end and high-voltage isolation. In those earlier devices, differential Hall plates and a magnetically coupled primary path provide high immunity to external magnetic fields and support reinforced or basic isolation ratings under UL 62368-1, and similar techniques underpin the ACS37200 architecture.

The ACS37200 arrives factory calibrated and UL 62368-1 certified, replacing a shunt resistor, isolation amplifier, and multiple passive components with a single 8-pin PSOF device. This simplifies layout around the high-current path, reduces bill of materials, and shortens safety review cycles because the isolation function is contained in a single certified component.

By combining the ultra-low-resistance primary conductor in the ACS37200 with the high-bandwidth, low-offset Hall signal conditioning approach seen in the ACS37002 family, Allegro offers designers a path to higher efficiency and power density without sacrificing measurement fidelity or isolation robustness.

Unfortunately, a datasheet for this part is only available upon request, so no pricing or technical information has been made available apart from a press release — the spiffy packaging and high current capacity warranted making Electronic Design’s readers aware of the part. During CES 2026, Allegro is booking 50-minute appointments at a nearby private suite (the company doesn’t have a booth presence at the show).

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