November 30, 2010
Worcester, MA – Allegro MicroSytems, LLC introduces 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 1.2 mΩ 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 thicknessof the copper conductor allows survival of the device at up to 5× 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.