LT4351CMS#PBF

LT4351 MOSFET Diode-OR Controller FEATURES DESCRIPTION n Low Loss Replacement for ORing Diode in Multiple The LT 4351 creates a near ideal diode using external Sourced Power Supplies single or back-to-back N-channel MOSFETs. This ideal n External N-Channel MOSFETs for High Current diode function permits low loss ORing of multiple power Capability sources. Power sources can easily be ORed together to n Internal Boost Regulator Supply for MOSFET increase total system power and reliability with minimal Gate Drive effect on supply voltage or efficiency. Disparate power n Wide Input Range: 1.2V to 18V supplies can be efficiently ORed together. n Fast Switching MOSFET Gate Control The IC monitors the input supply with respect to the load n Input Under and Overvoltage Detection and turns on the MOSFET(s) when the input supply is n STATUS and FAULT Outputs for Monitoring higher. If the MOSFETs R is sufficiently small, the DS(ON) n Internal MOSFET Gate Clamp LT4351 will regulate the voltage across the MOSFET(s) n Available in a 10-pin MSOP Package to 15mV. A STATUS pin indicates the MOSFET on-state. APPLICATIONS An internal boost regulator generates the MOSFET gate drive voltage. Low operating voltage allows for ORing of n Paralleled Power Supplies supplies as low as 1.2V. n Uninterrupted Supplies n High Availability Systems The LT4351 will disable power passage during undervolt- n N + 1 Redundant Power Supplies age or overvoltage conditions. These voltages are set by L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks resistive dividers on the UV and OV pins. The undervoltage and PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other threshold has user programmable hysteresis. Overvoltage trademarks are the property of their respective owners. detection is filtered to reduce false triggering. The LT4351 is available in a 10-pin MSOP package. TYPICAL APPLICATION Dual 5V Redundant Supply Si4862DY Si4862DY POWER 5V COMMON POWER 5V 5V SUPPLY SUPPLY 1 2 10F 10F 1 1 C LOAD 4.7H LOAD 4.7H 1F 1F V GATE OUT OUT GATE V IN IN MBR0530 MBR0530 V V DD DD MBR0530 MBR0530 LT4351 LT4351 SW STATUS STATUS SW 24.9k 24.9k 1% 1% UV UV FAULT FAULT 232 232 1% 1% OV GND GND OV 1.47k 1.47k 4351 TA01 1% 1% 4351fd 1LT4351 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V Voltage ................................................ 0.3V to 19V IN GATE 1 10 OUT OUT Voltage ............................................. 0.3V to 19V V 2 9 STATUS DD V 3 8 FAULT IN V Voltage .............................................. 0.3V to 30V DD SW 4 7 UV GND 5 6 OV FAULT, STATUS Voltages .......................... 0.3V to 30V MS PACKAGE FAULT, STATUS Current .......................................... 8mA 10-LEAD PLASTIC MSOP UV, OV Voltages ......................................... 0.3V to 9V T = 125C, = 120C/W JMAX JA SW Voltage .............................................. 0.3V to 32V Operating Temperature Range LT4351C .................................................. 0C to 70C LT4351I ............................................... 40C to 85C Junction Temperature (Note 2) ............................ 125C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) .................. 300C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT4351CMS PBF LT4351CMS TRPBF LTZZ 10-Lead Plastic MSOP 0C to 70C LT4351IMS PBF LT4351IMS TRPBF LTA1 10-Lead Plastic MSOP 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: