Allegro MicroSystems has released a fully integrated, small form factor, power monitoring IC with reinforced voltage isolation. Allegro’s ACS724 and ACS711 Current Sensor ICs are commonly used in internet connected power outlets and other IOT devices. The ACS71020 improves upon these popular ICs by including power sensing functions and by eliminating power and isolation components that would otherwise increase the cost and the size of customer systems. The ACS71020 IC builds upon our innovative Hall-effect current sensor IC technology by adding line voltage sensing (to voltage levels > 500 VRMS) and a dedicated metrology engine that digitally calculates detected power levels. This enables the first power monitor IC that can be powered from the same voltage supply as the system microprocessor, without needing digital isolators or multiple power supplies.

Allegro’s new power monitor IC simplifies common power measurements by offering digital computation of parameters including active, reactive and apparent power. These power values can be read out through I²C or SPI. The IC also includes dedicated pins for voltage zero crossing (suitable for light-dimming applications) and fast overcurrent fault detection (for sensing short-circuits). The ACS71020 eliminates the need for opto-couplers, dual output isolated power supplies and a current sense-resistor in single phase power monitoring applications.

The ACS71020 is housed in a single SOIC-16 wide body package that provides a reinforced isolation rating up to 517 Vrms. This monolithic IC provides makes it simple to add power monitoring to any AC or DC powered device.

The ACS71020 current sensor IC is programmed at Allegro for optimized accuracy measurement to either +/-15, +/-30, or +/-90 A and is priced at $1.79 in quantities of 1,000.