A 25A Hybrid Magnetic Current Sensor with 64mA Resolution, 1.8MHz Bandwidth, and a Gain Drift Compensation Scheme

Magnetic current sensors are used in switched-mode power supplies and motor drivers, where both galvanic isolation and wide bandwidth (BW) are desired. In CMOS, Hall-effect sensors are widely used, but their resistance results in a fundamental trade-off between BW and resolution. Coils have a differentiating characteristic and so can achieve much wider BW and resolution, but cannot sense DC.