LTC4088-1/LTC4088-2
High Efficiency Battery
Charger/USB Power Manager
with Regulated Output Voltage
Fea T Descrip T
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Switching Regulator Makes Optimal Use of Limited The LTC 4088-1/LTC4088-2 is a high efficiency USB
Power Available from USB Port to Charge Battery PowerPath controller and Li-Ion/Polymer battery char-
and Power Application ger. It includes a synchronous switching input regulator,
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180m Internal Ideal Diode Plus External Ideal Diode a full-featured battery charger and an ideal diode. De-
Controller Seamlessly Provide Low Loss Power Path signed specifically for USB applications, the LTC4088-1/
When Input Power is Limited or Unavailable LTC4088-2s switching regulator automatically limits its
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Automatic Charge Current Reduction Maintains 3.6V input current to either 100mA, 500mA or 1A via logic
Minimum V control. The LTC4088-1 powers-up with the charger off;
OUT
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Full Featured Li-Ion/Polymer Battery Charger the LTC4088-2 powers-up with the charger on.
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V Operating Range: 4.25V to 5.5V (7V Absolute
BUS
The switching input stage provides power to V where
OUT
MaximumTransient)
power sharing between the application circuit and the
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1.2A Maximum Input Current Limit
battery charger is managed. Charge current is automati-
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1.5A Maximum Charge Current with Thermal Limiting
cally reduced to maintain a regulated 3.6V V during
OUT
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Bat-Track Adaptive Output Control
low-battery conditions. As the battery is charged, V
OUT
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Slew Control Reduces Switching EMI
tracks V for high efficiency charging. This feature al-
BAT
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Low Profile (0.75mm) 14-Lead 4mm 3mm DFN Package
lows the LTC4088-1/LTC4088-2 to provide more power
to the application and eases thermal issues in constrained
a T
applications.
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Media Players
An ideal diode ensures that system power is available
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Digital Cameras
from the battery when the input current limit is reached
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GPS
or if the USB or wall supply is removed.
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PDAs
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Smart Phones
The LTC4088-1/LTC4088-2 is available in the low profile
14-Lead 4mm 3mm 0.75mm DFN surface mount
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and Bat-Track are tradmearks of Linear Technology Corporation. All other trademarks
package.
are the property of their respective owners. Protected by U.S. Patents, including 6522118.
Typical a T
Switching Regulator Efficiency to
System Load (P /P )
OUT BUS
High Efficiency Battery Charger/USB Power Manager
100
90
3.3H
WALL
80
SYSTEM
BAT = 4.2V
USB V SW V 70
BUS OUT
LOAD
D0 V
10F
OUTS
60
D1 GATE BAT = 3.3V
LTC4088-1/LTC4088-2
50
D2
40
CHRG BAT
CLPROG PROG C/X GND NTC 10F
30
+
20
8.2
Li-Ion V = 5V
BUS
2.94k 499
0.1F I = 0mA
10 BAT
408812 TA01a
10x MODE
0
0.01 0.1 1
I (A) 408812 TA01b
OUT
40881fc
1
EFFICIENCY (%)
ion pplica
ions pplica
ion uresLTC4088-1/LTC4088-2
a Te Maxi Mu M r a T p c F T
(Note 1)
TOP VIEW
V (Transient) t < 1ms, Duty Cycle < 1% .. 0.3V to 7V
BUS
NTC 1 14 D1
V (Static), BAT, CHRG, NTC, D0,
BUS
CLPROG 2 13 D0
D1, D2 .......................................................... 0.3V to 6V
V 3 12 SW
OUTS
I ....................................................................3mA
CLPROG
15
D2 4 11 V
BUS
I , I ................................................................2mA
C/X 5 10 V
PROG C/X OUT
PROG 6 9 BAT
I ......................................................................75mA
CHRG
CHRG 7 8 GATE
I .............................................................................2A
OUT
I ..............................................................................2A
DE PACKAGE
SW
14-LEAD (4mm 3mm) PLASTIC DFN
I .............................................................................2A
BAT
T = 125C, = 37C/W
JMAX JA
Maximum Operating Junction Temperature .......... 125C EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB
Operating Temperature Range .................40C to 85C
Storage Temperature Range .................. 65C to 125C
o r D i n F Ma T
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC4088EDE-1#PBF LTC4088EDE-1#TRPBF 40881 14-Lead (4mm x 3mm x 0.75mm) Plastic DFN 40C to 85C
LTC4088EDE-2#PBF LTC4088EDE-2#TRPBF 40882 14-Lead (4mm x 3mm x 0.75mm) Plastic DFN 40C to 85C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on nonstandard lead based finish parts.
For more information on lead free part markings, go to: