The ADM1170 is a Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. This is achieved using a pass FET with a current control loop that monitors the input current using a sense resistor. An internal charge pump is used to enhance the gate of the external high side N-channel FET. When an over current condition is detected the gate voltage of the FET is reduced to limit the current flowing through the sense resistor.