Current sensors simplify integration

Current shunt solutions require multiple components as well as additional PCB layers and heat sinks to meet thermal performance requirements, adding size, weight and design challenges. To address these concerns, Allegro MicroSystems, Inc. has announced the availability of the AC537220 high-power magnetic current sensor and the preliminary release of the ACS37041, claimed as the industry’s smallest leaded magnetic sensor.

(Source: Allegro MicroSystems, Inc.)

These current sensors target industrial, automotive and clean energy applications. They integrate the functions of a shunt resistor, shunt amplifier and other passive components in a single package. These solutions enable greater efficiency, reliability and system protection as well as a smaller bill of materials (BOM) compared to today’s discrete shunt resistor and op-amp-based solutions, Allegro said.

The ACS37220, housed in an EZ 4 × 4-mm QFN package, is designed to replace high-power sense resistors and can be used in high-current monitoring applications up to 200 A. The device targets low voltage (< 100 V), high current monitoring applications and in-line current sensing in motor drives, clean energy storage, data-center server DC/DC power supplies and data-center battery backup.

This high-power-density 200 A, 150-kHz magnetic current sensor includes an overcurrent fault output with user-configurable threshold to provide fast short-circuit detection for enhanced system protection. The QFN package features a low internal conductor resistance of 100 μΩ for low power loss and high inrush current withstand capability.

Offering a high level of integration in a compact SOT23-W package, the ACS37041 simplifies current measurement and eliminates the need for external shunt resistors and op-amps, reducing board space and component count. It is suited for a wide range of current sensing applications up to 30 A with high accuracy over the full operating temperature range, targeting space-constrained applications.

This Hall-effect current sensor’s inherent galvanic isolation (functionally isolated for rails to 100 V) enhances system safety and simplifies integration by eliminating the need for complex isolation schemes, according to Allegro.

An integrated conductor with low resistance for current measurement reduces power losses and improves efficiency, Allegro said. Applications include motor control, battery management, power supplies, clean-energy string and micro inverters and personal mobility e-bikes and e-scooters.

The ACS37041 is a pre-release product. A datasheet can be requested via the website. The AC537220 is available for purchase via authorized distributors including Arrow, DigiKey and Mouser.