The ADM1171 is a hot swap controller that safely enables a printed circuit board to be removed and inserted to a live backplane. This is achieved using an external N-channel power MOSFET with a current control loop that monitors the load current through a sense resistor. An internal charge pump is used to enhance the gate of the N-channel FET. When an overcurrent condition is detected， the gate voltage of the FET is reduced to limit the current flowing through the sense resistor. During an overcurrent condition， the TIMER cap determines the amount of time the FET remains at a current limiting mode of operation until it is shut down. The ON （ON-CLR） pin is the enable input for the device and can be used to monitor the input supply voltage. The ADM1171 operates with a supply voltage ranging from 2.7 V to 16.5 V.

　　The ADM1171 features soft start to provide the user with a capacitor programmable ramping reference to the internal current sense comparator. This provides a linearly increasing current limit at startup at a rate set by CSS. This helps to reduce and limit large inrush currents.

　　The ADM1171 also features a current sense output （CSOUT） pin. The voltage on the CSOUT pin represents the voltage drop across the sense resistor gained up by a factor of 20.

　　This device is available in two options： the ADM1171-1 with automatic retry for overcurrent fault and the ADM1171-2 with latch-off for an overcurrent fault. Toggling the ON （ON-CLR） pin resets a latched fault. The ADM1171 is packaged in an 8-lead TSOT.