Current Sensors
Precision current sensing for efficient, high-voltage designs.
Allegro’s current sensors deliver galvanic isolation, lossless operation, and high-precision accuracy—enabling maximum efficiency and power density in compact systems. Designed for EV traction and auxiliary inverters, DC-DC converters, on-board chargers, solar inverters, and industrial power systems, our solutions offer isolation ratings up to 5 kVRMS, ultra-low conductor resistance down to 0.1 milliohms, and bandwidths up to 5 MHz for GaN/SiC power electronics.
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Field Current Sensors
Achieve unparalleled accuracy in current sensing with our field current sensors, designed for robust performance with stray field immunity and advanced diagnostics in demanding automotive and industrial applications.
Integrated Current Sensors
Our integrated current sensors combine precision measurement with built-in isolation for compact, high-efficiency designs.
Documentation & Resources
Blog
Beyond the Datasheet: Mastering Current Sensing Selection
Master current sensor selection with expert guidance on technology trade-offs to design safer, more efficient, dependable solutions.
Technical Article
Rethink PCB Current Sensing
This article will discuss two new innovative approaches to measure currents up to 600 A in PCB: a near-lossless Hall-based current sensor with an integrated conductor and a non-invasive standalone core-free and shield-free differential Hall current sensor.
Technical Article
Breaking the Density Barrier: A Technical Deep Dive into Simplified SiC Gate Drive
Learn how Power-Thru™ isolated SiC gate drivers eliminate the need for bulky external bias supplies, drastically reducing BOM count and PCB size by up to 50%. Solve EMI and power density challenges in your next high-voltage design.
Technical Article
New 400 kHz Current Sensors Enable More Sustainable Designs in Switch-Mode Power Designs
Really Cool. Really Efficient. New 400 kHz current sensors enable more sustainable designs in switch-mode power designs.
Technical Article
Solar Energy Systems – New Market Trends in Current Sensing
P0103 - As solar installations grow larger and more ambitious by the day, new trends in current sensing are emerging for this expanding energy market.
Application Note
An Effective Method for Characterizing System Bandwidth in Complex Current Sensor Applications
This application note describes multiple methods for measuring
and characterizing system bandwidth, with a focus on
the impulse response method. Allegro’s ACS720 is the perfect device to validate the test methods outlined here.
Application Note
High-Current Measurement with Allegro Current Sensor IC and Ferromagnetic Core: Impact of Eddy Currents
AN296162 - The technique of measuring bus bar current with a surrounding ferromagnetic core is common knowledge. For highcurrent measurement above 200 A, Allegro recommends using a linear IC of the A136x family
Technical Article
Allegro is Driving the Future with Reliable eMobility Solutions
Techmezine speaks with Andreas P. Friedrich on Allegro’s Battery Management Solutions and latest innovation for EV.
Brochure
Brochure: Industry's First ASIL-C Field Current Sensor for eMobility
The ACS37601 is Allegro’s latest and most advanced linear Hall-effect sensor IC for core-based current sensing, developed in accordance with the ISO 26262 functional safety standard to achieve an ASIL C safety rating.
Brochure
Brochure: Driving Change by Advancing Personal Mobility Through Cutting-Edge Technology
Our advanced sensor and power IC solutions are engineered specifically to meet the unique requirements of these designs, providing superior performance and reliability in harsh environments and under complex operating conditions.
Application Note
How to Analyze and Compare Allegro Current Sensor and ADC Error Components
AN296282: Allegro offers a wide variety of current sensors with analog voltage outputs, and in many applications, an analog-to-digital converter (ADC) converts the output voltage to a binary code.
Application Note
Increasing System Safety using the A1365 Programmable Linear Hall-Effect Sensor IC with Self-Test Diagnostic Mode
As safety goals multiply throughout the system design process, customers demand smart sensors that can be used to diagnose abnormalities in a system. The built-in Self-Test mode of the A1365 grants users such insight into their systems.
Application Note
Achieving Closed-Loop Accuracy in Open-Loop Current Sensors
Closed-loop current sensing technology is employed in many industrial and automotive applications for accurate current sensing. Allegro MicroSystems has developed magnetic-based current sensor IC solutions that achieve near closed-loop accuracy using an open-loop topology.
Technical Article
Magnetic Current Sensing Drives Vehicle Electrification
Modern cars have become increasingly power hungry. Even the “least electrified” vehicles include advanced electronics for infotainment, safety, and engine control. Fully electric vehicles further add high-voltage power domains to charge and drive. Each of these systems shares the need for power monitoring and control, and this is where current sensors are used.
Application Note
PCB Ground Plane Optimization for Coreless Current Sensor Applications
AN296277 - This application note provides guidelines on how a PCB ground plane around the sensor location should be designed to achieve optimum performances.
Application Note
New Approaches to High-Efficiency Current Sensing: Integrated Hall Sensor ICs Save Power and Space
AN296100: Allegro current sensor ICs allow design engineers to use Hall-effect based current sensor ICs in new applications where increased energy efficiency or new operating features are required. Wherever current sensing is needed, an integrated Hall-effect IC can provide a solution.
Application Note
Current Sensing for Power Delivery
AN296256 - This article will discuss the advantages of various current sensing methods in power delivery.
Video
ACS780 & ACS781: High Current Density Fully Integrated Current Sensor ICs
Allegro’s new family of fully integrated current sensor linear ICs in a new core-less package designed to sense AC and DC currents up to 100 A.
Video
ACS712 Low-Noise 2100 VRMS Hall-Effect Current Sensor IC
The Allegro ACS712 provides economical and precise solutions for AC or DC current sensing in industrial, commercial, and communications systems. The device package allows for easy implementation by the customer. Typical applications include motor control, load detection and management, switched-mode power supplies, and overcurrent fault protection.
Brochure
Brochure: Integrated Power Monitoring with the ACS37800
Allegro’s ACS37800 offers its customers the capability to easily monitor and optimize the energy efficiency of power supplies, lighting, and motor control sub-systems in connected building automation solutions while simplifying the system design.
Application Note
ACS37610 Busbar Geometry and Design Techniques for Coreless Differential Current Sensors
AN296194 - The purpose of this application note is to offer guidelines for selecting the optimum combination of ACS37610 and busbar geometry for a given current sensor application and its specific requirements.
Application Note
Notched Busbar Design Guidelines For Coreless ACS37610 Differential Current Sensor
AN296231 - This application note focuses on how a busbar should be designed to achieve optimum performance with the ACS37610 coreless current sensor.
Application Note
Convenient and Isolated Power Measurements via SPI or I2C using ACS71020 or ACS37800 Power Monitoring ICs
AN296180 - This application note describes the I2C and SPI interfaces on the ACS71020/ACS37800 Power Monitoring ICs from Allegro MicroSystems.
Application Note
Explanation of Error Specifications for Allegro Linear Hall-Effect based Current Sensor ICs
AN296181 - Determining the accuracy of a system requires knowledge of the error introduced by each component. When looking at Allegro current sensor datasheets, the total error line item is a good approximation of the worst-case error seen in application.
Application Note
Understanding Linearity Error for the ACS70310 Above 2000 G
AN296206 - The goal of this application note is to illustrate and discuss the linearity error of the ACS70310 when sensing fields greater than 2000 G.
Application Note
Guidelines for Designing a Busbar with Notch for Allegro's ACS37612 Differential Coreless Current Sensor
AN296188 - This application note offers guidelines for achieving optimum busbar and notch designs using the Allegro ACS37612 coreless current sensor
Application Note
Hysteresis Offset Error In Hall-Effect Current Sensors Using Soft Ferromagnetic Concentrator Cores
AN296182 - When measuring busbar current with a surrounding soft ferromagnetic concentrator cores, Allegro recommends using a linear IC, such as the A1365, A1367, or ACS70310, in conjunction with a ferromagnetic core for high-current measurement (above 200 A).
Application Note
I2C Addressing and Fault Monitoring Using The ACS71020 or ACS37800 Power Monitoring IC Digital Input Output Pins
AN296172 - This application note describes methods of setting the I2C slave address of the ACS71020/ACS37800 and the added functionality of the digital input-output (DIO) pins when operating in I2C mode.
Brochure
Brochure: Innovative Current Sensor ICs
Allegro MicroSystems has been driving innovation in the current sensor industry for more than 17 years, with a history of first-to-market products that give our customers a competitive edge. Our advanced ICs help you achieve higher efficiency and power density in your designs.
Application Note
Mitigating Interference while Measuring High Frequency, High Current Transient Responses
AN296155 - This application note will demonstrate techniques on how to avoid coupling the field from high-current transients onto the signal and power lines of current sensors in order to avoid a perceived distortion of the output.
Application Note
Overcurrent Fault Detection Using ACS37610 Coreless Current Sensor
AN269241 - This application note explains how the Overcurrent-Fault (OCF) feature of Allegro ACS37610 device can be used in application to reliably detect overcurrent conditions and how it can be configured to optimize accuracy and cover different application needs.
Brochure
Brochure: Solar Energy Harvesting
Allegro’s current sensor ICs are ideal for use with solar applications, which include electronic subsystems like solar combiner boxes, DC/DC converters for maximum power point tracking (MPPT), and DC-AC inverters.
Brochure
Brochure: Current Sensing for Vehicle Electrification
Charge into the future of vehicle electrification with the world's #1 supplier of current sensor ICs for leading EV applications.
Application Note
ACS37600 Reference PCB Design for Current Sensing Module Applications
AN296205 - The aim of this document is to provide guidelines for designing a PCB for the ACS37600 while minimizing possible undershoots/overshoots due to a fast current step response.
Application Note
Material Selection and Geometry Considerations for High Current Sensing Magnetic Flux Concentrator Designs
AN296245 - Core material selection, geometry, and air gap dimensions will all impact the performance of the flux concentrator. This note will explain each of these factors and provide a detailed guide for design of a magnetic flux concentrator.