LTC1473_15 Datasheet, PDF (1/16 Pages) Linear Technology – Dual PowerPath Switch Driver

LTC1473
Dual PowerPath^TM
Switch Driver
FEATURES
s _{Power Path Management for Systems with Multiple}
DC Sources
s _{All N-Channel Switching to Reduce Power Losses and}
System Cost
s _{Switches and Isolates Sources Up to 30V}
s _{Adaptive High Voltage Step-Up Regulator for N-Channel}
Gate Drive
s _{Capacitor Inrush and Short-Circuit Current Limited}
s _{User-Programmable Timer to Limit Switch Dissipation}
s _{Small Footprint: 16-Pin Narrow SSOP}
U
APPLICATIO S
s _{Notebook Computers}
s _{Portable Instruments}
s _{Handi-Terminals}
s _{Portable Medical Equipment}
s _{Portable Industrial Control Equipment}
DESCRIPTIO
The LTC^®1473 provides a power management solution for
single and dual battery notebook computers and other
portable equipment. The LTC1473 drives two sets of back-
to-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.
PowerPath is a trademark of Linear Technology Corporation.
TYPICAL APPLICATION
MBRD340
BAT1
DCIN
C_TIMER
4700pF
MMBD2838LTI
1µF
1µF
FROM POWER
MANAGEMENT
µP
1mH*
MMBD914LTI
1
LTC1473
16
IN1
GA1
2
IN2
15
SAB1
3
DIODE
14
GB1
4
TIMER
SENSE^{+ 13}
5 _V+
SENSE^{– 12}
6
V_GG
11
GA2
7
SW
10
SAB2
8
GND
9
GB2
BAT2
*COILCRAFT 1812LS-105XKBC
Si9926DY
Si9926DY
R_SENSE
0.04Ω
C_OUT
INPUT OF SYSTEM
HIGH EFFICIENCY DC/DC
SWITCHING REGULATOR
(LTC1735, ETC)
1473 TA01
1