Allegro MicroSystems, LLC has announced two new current sensor ICs that are economical and precise solutions for AC or DC current sensing in industrial and commercial systems.
Allegro’s ACS722 and ACS723 are highly accurate devices that offer improved isolation performance, low power consumption, and a wide operating temperature range with near zero magnetic hysteresis in a surface mount package. The small package is suited for space constrained applications while also saving costs due to reduced board area, yet provides a 4800 VRMS isolation rating, the highest available from Allegro surface mount current sensor ICs. Typical applications include motor control, solar inverters, home automation and monitoring as well as those applications requiring reinforced isolation ranges. (Please note that these devices are not designed for use in automotive applications.)
Allegro’s ACS722 and ACS723 consist of 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 optimized through the close proximity of the magnetic field to the Hall transducer. A precise, proportional voltage is provided by the low-offset, chopper-stabilized BiCMOS Hall IC, which includes Allegro’s patented digital temperature compensation, resulting in extremely accurate performance over temperature. The output of the device has a positive slope when an increasing current flows through the primary copper conduction path (from pins 1 through 4, to pins 5 through 8), which is the path used for current sensing. The internal resistance of this conductive path is 0.85 mΩ typical, providing low power loss. The terminals of the conductive path are electrically isolated from the sensor leads (pins 9 through 16). This allows the current sensor ICs to be used in high-side current sense applications without the use of high-side differential amplifiers or other costly isolation techniques.
Both devices are provided in a low profile surface mount SOIC16 package. The leadframe is plated with 100 percent 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 devices are fully calibrated prior to shipment from the factory. The ACS722KMA and the ACS723KMA are both priced at $2.19 in quantities of 1,000.