UCC3918

ą UCC3918 LOW ONĆRESISTANCE HOT SWAP POWER MANAGER D Integrated 0.075-Ω Power MOSFET D 3 V to 6 V Operation D External Analog Control of Fault Current from 0 A to 4 A D Independent Analog Control of Current Limit Up to 5 A D Fast Overload Protection D Unidirectional Switch D Minimal External Components D 1-µA ICC When Disabled D Programmable On Time D Programmable Start Delay D Fixed 3% Duty Cycle SLUS384B – NOVEMBER 1999 – REVISED JUNE 2000 DP PACKAGE (TOP VIEW) VIN VIN VIN GND* GND* FAULT SHTDWN IFAULT 1 2 3 4 5 6 7 8 16 VOUT 15 VOUT 14 VOUT 13 GND* 12 GND* 11 NC 10 CT 9 IMAX Pin 5 serves as the lowest impedance to the electrical ground. Pins 4, 12, and 13, serve as heat sink/ground. These pins should be connected to large etch PCB areas to help dissipate heat. description The UCC3918 low on-resistance hot swap power manager provides complete power management, hot swap capability, and circuit breaker functions. The only components needed to operate the device, other than supply bypassing, are a timing capacitor, and two programming resistors. All control and housekeeping functions are integrated, and externally programmable. These include the fault current level, maximum output sourcing current, maximum fault time, and startup delay. In the event of a constant fault, the internal fixed 3% duty cycle ratio limits the average output power. The IFAULT pin allows linear programming of the fault level current from 0 A to 4 A. Fast overload protection is accomplished by a...