TEXAS INSTRUMENTS TPS2421-2DDA .

The TPS2421-2DDA is an integrated Hot Swap FET Controller provides highly integrated hot swap power management and superior protection in applications where the load is powered by busses up to 20V. This is well suited to standard bus voltages as low as 3.3V because of the maximum-UV turn-on threshold of 2.9V. It is very effective in systems where a voltage bus must be protected to prevent shorts from interrupting or damaging the unit. It has multiple programmable protection features. Load protection is accomplished by a non-current limiting fault threshold, a hard current limit and a fault timer. The current dual thresholds allow the system to draw short high current pulses, while the fault timer is running, without causing a voltage droop at the load. An example of this is a disk drive startup. This technique is ideal for loads that experience brief high demand, but benefit from protection levels in-line with their average current draw.