Solid State Supplies has availability of a Hall-effect linear current sensor IC from Allegro MicroSystems. The ACS711 is a cost-efficient device that provides accurate AC or DC current sensing in low-voltage audio, communications systems, white goods, industrial power supplies, lighting, and automotive applications. Typical uses include circuit protection, current monitoring, and motor and inverter control.
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, 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 signal to the Hall transducer. Full-scale sensing options within the ACS711 family include ±12.5 and ±25A. 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 1.2mOhm typical, providing a non-intrusive measurement interface that saves power in applications that require energy efficiency. The device is optimised 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 low AC or DC working voltage applications. The thickness of the copper conductor allows survival of the device at up to five times over-current conditions. The device is provided in a single small-form-factor surface-mount SOIC8 package, and obviating the need for an external sense resistor. Other key features include: economical low- and high-side current sensing, output voltage proportional to AC or DC currents, overcurrent active low FAULT trips and latches at 100% of full-scale current, low-noise analogue signal path, 100kHz bandwidth, 3.3 to 5.5V single-supply operation, integrated electrostatic shield for output stability, factory-trimmed for accuracy, extremely stable output offset voltage, zero magnetic hysteresis, and ratiometric output from supply voltage
