LTC1473 Datasheet | Linear Technology

LTC1473 Dual Power Path TM Switch Driver Features s s DESCRIPTIO s s s s s Power Path Management for Systems with Multiple DC Sources All N-Channel Switching to Reduce Power Losses and System Cost Switches and Isolates Sources Up to 30V Adaptive High Voltage Step-Up Regulator for N-Channel Gate Drive Capacitor Inrush and Short-Circuit Current Limited User-Programmable Timer to Limit Switch Dissipation Small Footprint: 16-Pin Narrow SSOP The LTC®1473 provides a power management solution for single and dual battery notebook puters and other portable equipment. The LTC1473 drives two sets of backto-back N-channel MOSFET switches to route power to the input of the main system switching regulator. An internal boost regulator provides the voltage to fully enhance the logic level N-channel MOSFET switches. The LTC1473 senses current to limit surge currents both into and out of the batteries and the system supply capacitor during switch-over transitions or during fault conditions. A user-programmable timer monitors the time the MOSFET switches are in current limit and latches them off when the programmed time is exceeded. A unique “2-diode mode” logic ensures system start-up regardless of which input receives power first. , LTC and LT are registered trademarks of Linear Technology Corporation. Power Path is a trademark of Linear Technology Corporation. U APPLICATIO S s s s s s Notebook puters Portable Instruments Handi-Terminals Portable Medical Equipment Portable Industrial Control Equipment TYPICAL APPLICATION MBRD340 Si9926DY BAT1 MMBD2838LTI 1 DCIN FROM POWER MANAGEMENT µP 2 3 4 CTIMER 4700p F 1µF 1µF MMBD914LTI 1m H- 5 6 7 8 LTC1473 IN1 IN2 DIODE TIMER V+ VGG SW GND GA1 SAB1 GB1 16 15 14 RSENSE 0.04Ω COUT INPUT OF SYSTEM HIGH EFFICIENCY DC/DC SWITCHING REGULATOR (LTC1735, ETC) 13 SENSE + 12 SENSE - 11 GA2 10 SAB2 9 GB2 BAT2 - COILCRAFT 1812LS-105XKBC Si9926DY 1473...