EMI Robust Comparator Design for Protection Features of Smart Power Switches

In the field of automotive smart power switches, the integrity of the chip’s temperature signal processing and overtemperature recognition are critical. This paper presents a robust input stage for a comparator designed to withstand electromagnetic interference (EMI) while maintaining accuracy. We present a novel design that incorporates hysteresis and uses linearisation techniques to enhance immunity to radio frequency (RF) interference. Our results show a significant improvement in the electromagnetic immunity of the overtemperature protection mechanism. We validate our results with direct power injection (DPI) simulations comparing the standard input topology with the EMI improved one.