Allegro Micro Announces New Hall-Effect Linear Current Sensor IC

Allegro MicroSytems, Inc. introduced a new Hall-effect linear current sensor IC that provides economical and precise solutions for ac or dc current sensing in low-voltage audio, communications systems, white goods, and automotive applications. Typical applications include circuit protection, current monitoring, and motor and inverter control.

Allegro’s 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 which 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 1.2mΩ typical, 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 leads (pins 5 through 8), providing sufficient internal creepage and clearance dimensions for a low ac or dc working voltage applications. The thickness of the copper conductor allows survival of the device at up to 5x overcurrent conditions.

The ACS711 is provided in a small, surface mount SOIC8 package. The leadframe 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.

The devices are priced (for 1,000 pieces) between $0.97 to $1.03.