Hall-effect current sensor has 1MHz bandwidth

May 03, 2016 // By Julien Happich
Allegro MicroSystems Europe has released its first ever 1MHz bandwidth Hall-effect current sensor IC, boasting a 210ns response time.

The ACS730 provides an economical and precise solution for AC or DC current sensing and is aimed at industrial, commercial, and communications systems for motor control, load detection and management, switched-mode power supplies, and over-current fault protection.

Delivered in a SOIC-8 package, the device combines a precise, low-offset, linear Hall-sensor circuit with a copper conduction path located near the surface of the die. Applied current flowing through this copper conduction path generates a magnetic field which is sensed by the integrated Hall IC and converted into a proportional voltage. Device accuracy is optimised through the close proximity of the magnetic field to the Hall transducer. A precise, proportional voltage is provided by the Hall IC, which is programmed for accuracy after packaging.

The output of the device has a positive slope when an increasing current flows through the primary copper conduction path (from pins 1 and 2, to pins 3 and 4), which is the path used for current sensing. The internal resistance of this conductive path is typically 1.2 mΩ, providing low power loss.  The terminals of the conductive path are electrically isolated from the sensor leads (pins 5 through 8). This allows the ACS730 current sensor IC to be used in high-side current sense applications without the use of high-side differential amplifiers or other costly isolation techniques. 

Visit Allegro MicroSystems at www.allegromicro.com