Reverse Voltage Protection Circuits for Power MOSFETs in Low Dropout Power Applications

Abstract

This paper proposed three reverse voltage protection circuits for the power MOSFETs in low dropout power applications. Power devices are vulnerable to instantaneous current overshoot when the input voltage is lower than the output voltage. Compared with conventional solutions using diode for reverse current block, the proposed three structures consume fewer voltage drop during normal operation. The first design is suitable for applications with wide output ranges but requires the largest die area. The other two solutions are for applications with low output voltages, and are characterized with effective area arrangement and dead-zone free control, respectively. The proposed three protection structures require 126.2%, 12.25% and 43.05% extra die area of the power devices, respectively.