The TPS2390 and TPS2391 integrated circuits are hot swap power managers optimized for use in nominal –48-V systems. They are designed for supply voltage ranges up to –80 V, and are rated to withstand spikes to –100 V. In conjunction with an external N-channel FET and sense resistor, they can be used to enable live insertion of plug-in cards and modules in powered systems. Both devices provide load current slew rate and peak magnitude limiting, easily programmed by sense resistor value and a single-external capacitor. They also provide single-line fault reporting, electrical isolation of faulty cards, and protection against nuisance overcurrent trips. The TPS2390 latches off in response to current faults, while the TPS2391 periodically retries the load in the event of a fault.