Allegro MicroSystems unveils ACS37100 TMR current sensor for optimal protection, control of wide bandgap power electronics

Allegro MicroSystems, a global provider of power and sensing technologies for motion control and energy-efficient systems, introduced what it said is the industry's first commercially available magnetic current sensor to achieve 10 MHz bandwidth, featuring Allegro’s advanced XtremeSense TMR (tunneling magnetoresistance) technology.

The new ACS37100 TMR current sensor helps power system designers master the control signal chain and unlock the full potential of fast-switching GaN and SiC FETs. Tailored to the needs of electric vehicles (EVs), clean energy power conversion systems, and AI data center power supplies, Allegro MicroSystems said the ACS37100 achieves an industry-leading 50 ns response time, providing the high-fidelity data needed for optimal efficiency and protection in demanding high-frequency applications.

GaN to SiC migration

Allegro MicroSystems said the migration to GaN and SiC promises greater power density and efficiency, but their faster switching speeds create significant control challenges. At sub-megahertz frequencies, conventional magnetic current sensors lack the speed and precision to provide the high-fidelity, real-time data required for stable control and protection loops. This can leave advanced systems vulnerable to damage and may prevent them from operating at their full potential.

The company added that its ACS37100 is engineered to solve this control challenge. Its bandwidth and response time provide the high-fidelity current sense feedback essential for demanding control loops in high-speed switching applications. This magnetic current sensor enables designers to confidently and reliably control faster systems, maximize efficiency and increase power density. Leveraging advanced TMR technology, the device delivers low noise of 26 mA root mean square (RMS) across the full 10 MHz bandwidth - enabling precise, high-speed current measurements for more accurate and responsive system performance.

“The ACS37100 marks a critical inflection point for magnetic sensors. Our TMR technology is enabling current sensors that are ten times faster and four times lower noise versus typical Hall-based products,” said Matt Hein, business line director of current sensors at Allegro MicroSystems. “This leap in performance solves important challenges in high-voltage power conversion, especially related to wide bandgap solutions.”

The ACS37100 is engineered to minimize energy loss while maximizing operational efficiency and reliability, making it the ideal choice for a variety of automotive and industrial uses like EV charging, clean energy power conversion, and AI data center power supplies.

Allegro MicroSystems released the following features and benefits of the ACS37100:

• Highest bandwidth: DC to 10 MHz
• Fast response time: 50 ns 
• Low noise: 26 mA_RMS at full 10 MHz bandwidth
• Integrated Reinforced Isolation: 5 kV (60 seconds per UL 62368-1)
• Low loss: 1.2 mΩ internal conductor resistance
• Automotive Grade 0: -40°C to +150°C operating temperature range

The ACS37100 is available in an industry-standard SOICW-16 package that supports a working reinforced isolation up to 565 V_RMS (basic 1,097 V_RMS) with 8 mm creepage and clearance. It features a voltage reference output and an adjustable overcurrent fault.