The UCC3920 Low RDSon Hot Swap Power Manager provides complete power management, hot swap capability, and circuit breaker functions. The only component needed to operate the device, other than supply bypassing, is the fault timing capacitor, CT. All control and housekeeping functions are integrated and externally programmable. These include the fault current level, maximum output sourcing current, maximum fault time, and start up delay. In the event of a constant fault, the internal fixed 2% duty cycle ratio limits the average output power. The internal 3 bit DAC allows programming of the fault level current from 0mA to 500mA with 250mA resolution, and from 500mA to 3A with 500mA resolution. The IMAX control pin sets the maximum sourcing current to 1A above the fault level when driven low, and to a full 4A when driven high for applications which require fast output charging.