The TPS2556-Q1 and TPS2557-Q1 are current-limited, power-distribution switches using N-channel MOSFETs for applications that might encounter short circuits or heavy capacitive loads . This device allows the user to program the current-limit threshold between 500 mA and 5 A (typical) via an external resistor. This device incorporates an internal charge pump and the gate-drive circuitry necessary to drive the N-channel MOSFET. The charge pump supplies power to the driver circuit and provides the necessary voltage to pull the gate of the MOSFET above the source. The charge pump operates from input voltages as low as 2.5 V and requires little supply current. The driver controls the gate voltage of the power switch. The driver incorporates circuitry that controls the rise and fall times of the output voltage to limit large current and voltage surges and provides built-in soft-start functionality. The TPS2556-Q1 and TPS2557-Q1 family limits the output current to the programmed current-limit threshold I_OS during an overcurrent or short-circuit event by reducing the charge-pump voltage driving the N-channel MOSFET and operating it in the linear range of operation. The result of limiting the output current to I_OS reduces the output voltage at OUT by no longer fully enhancing the N-channel MOSFET.