The LTC4224 Dual Low Voltage Hot Swap™controller allows a board to be safely inserted and removed from a live backplane. It controls two supplies with external N-channel MOSFETs and operates with one supply as low as 1V provided the other supply is 2.7V or greater. The LTC4224 can ramp up the supplies in any order and at adjustable ramp rates. To minimize the number of external components and PCB area, the gate capacitor is optional, all timing delays are generated internally, and theONpins have integrated pull-up currents.Protection against overcurrent faults is provided by a fast-acting current limit and timed circuit breakers. AFAULTpin signals overcurrent faults. The LTC4224-1 remains off after a fault, while the LTC4224-2 automatically tries to apply power again after a four second cool-down period.ApplicationsOptical NetworkingLow Voltage Hot SwapElectronic Circuit Breakers