The LT4256-3CGN#PBF is a positive high voltage Hot Swap Controller with open-circuit detect. It allows a board to be safely inserted and removed from a live backplane. An internal driver controls the high side N-channel MOSFET gate for supply voltages ranging from 10.8 to 80V. The part features an open-circuit detect (OPEN) output that indicates abnormally low load current conditions. The LT4256-3 also 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, the PWRGD output asserts low and the LT4256-3 either automatically restarts after a time-out delay or latches off until the UV pin is cycled low (depending on the status of the RETRY pin). The PWRGD output indicates when the output voltage rises above a programmed level. An external resistor string from VCC provides programmable undervoltage and overvoltage protection.
Allows safe board insertion and removal from a live backplane
Foldback current limiting
Open circuit and overcurrent fault detect
Drives an external N-channel MOSFET
Programmable supply voltage power-up rate
Automatic retry or latched off operation after overcurrent fault
(EN)
