ACS711 Hall Effect Linear Current Sensor

The Allegro ACS711 provides economical and precise solutions for AC or DC current sensing in <100 V audio, communications systems, and white goods.

The device consists of a 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 that is sensed by the integrated Hall IC and converted into a proportional voltage. Device accuracy is optimized through the close proximity of the magnetic signal to the Hall transducer.

The output of the device has a positive slope proportional to the current flow from IP+ to IP- (pins 1 and 2 to pins 3 and 4). The internal resistance of this conductive path is 0.6 mΩ for the EX package, and 1.2 mΩ for the LC package, providing a non-intrusive measurement interface that saves power in applications that require energy efficiency.

The ACS711 is optimized for low-side current sensing applications, although the terminals of the conductive path are electrically isolated from the sensor IC leads, providing sufficient internal creepage and clearance dimensions for a low AC or DC working voltage applications. The thickness of the copper conductor allows the survival of the device at up to 5× overcurrent conditions.

The ACS711 is provided in small, surface-mount packages: SOIC8 and QFN12. The lead frame is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board assembly processes. Internally, the device is Pb-free, except for flip-chip high-temperature Pb-based solder balls, currently exempt from RoHS. The device is fully calibrated prior to shipment from the factory.

Applications

• Short-circuit and overpower detection in audio
• Motor and pump control in white goods
• General power supply monitoring