A new MagFET-based integrated current sensor highly immune to EMI

This paper deals with the susceptibility to radio frequency interference of the integrated circuits used to monitor the current of power devices. A circuit based on the mirroring principle of common use in commercial devices is first considered, then a new contact-less fully integrated current sensor based on the Hall effect is proposed. The design of this current sensor is shown in detail and its susceptibility to radio frequency interference is investigated through time-domain simulations. The results of these analyses are presented then compared with those obtained from similar analysis carried out on a conventional (wired) current sensor.