The LT4256-1/LT4256-2 are high voltage Hot Swap™controllers that allow a board to be safely inserted and removed from a live backplane. An internal driver drives an external N-channel MOSFET switch to control supply voltages ranging from 10.8V to 80V.The LT4256-1/LT4256-2 features an adjustable analog foldback current limit. If the supply remains in current limit for more than a programmable time, the N-channel MOSFET shuts off and the PWRGD output asserts low. The LT4256-2 automatically restarts after a time-out delay. The LT4256-1 latches off until the UV pin is cycled low.The PWRGD output indicates when the output voltage rises above a programmed level. An external resistor string from VCCprovides programmable undervoltage protection.The LT4256 can be used as an upgrade to LT1641 designs.The LT4256-1 and LT4256-2 are available in an 8-pin SO package that is pin compatible with the LT1641.Retry / Latch OffFeaturesPackageLT4256-1Latch OffUVSO-8LT4256-2RetryUVSO-8LT4256-3Latch Off or RetryUV/OV, Open Circuit DetectSSOP-16ApplicationsHot Board InsertionElectronic Circuit Breaker/Power BussingIndustrial High Side Switch/Circuit Breaker24V/48V Industrial/Alarm SystemsIdeally Suited for 12V, 24V and 48V Distributed Power Systems48V Telecom Systems