CMOS microsystem for AC current measurement with galvanic isolation

In this paper, we present an integrated AC current sensor based on sensitivity-optimised horizontal Hall effect devices (HHDs) and a differential readout chain. It has been designed for 5A nominal AC current measurement with 5 kV galvanic isolation and 0.5% accuracy over 1.5 kHz bandwidth, which allows up to 30/sup th/ (25 th) harmonic detection in 50 Hz (60 Hz) applications. From the sensing element to the instrumental chain's output the signal conditioning is exclusively performed by low-noise standard CMOS analog blocks. Moreover the whole microsystem features a mixed signal structure dedicated to auto-balancing.