LTC3554/LTC3554-1/
LTC3554-2/LTC3554-3
Micropower USB Power
Manager with Li-Ion Charger
and Two Step-Down Regulators
Fea T Descrip T
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10A Standby Mode Quiescent Current (All Outputs On) The LTC 3554 family* are micropower, highly integrated
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Seamless Transition Between Input Power Sources: power management and battery charger ICs for single-cell
Li-Ion/Polymer Battery and USB Li-Ion/Polymer battery applications. They include a
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240m Internal Ideal Diode PowerPath manager with automatic load prioritization,
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Dual High Efficiency Step-Down Switching Regulators a battery charger, an ideal diode and numerous internal
(200mA I ) with Adjustable Output Voltages protection features. Designed specifically for USB applica-
OUT
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Pushbutton On/Off Control with System Reset tions, the LTC3554 power managers automatically limit
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Reset Time: 5 sec (LTC3554/LTC3554-1), input current to a maximum of either 100mA or 500mA.
14 sec (LTC3554-2/LTC3554-3) Battery charge current is automatically reduced such that
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Full Featured Li-Ion/Polymer Battery Charger the sum of the load current and the charge current does
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Programmable Charge Current with Thermal Limiting not exceed the selected input current limit.
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Instant-On Operation with Discharged Battery
The LTC3554 also includes two synchronous step-down
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Battery Float Voltage: 4.2V (LTC3554/LTC3554-2/
switching regulators as well as a pushbutton controller.
LTC3554-3), 4.1V (LTC3554-1)
With all supplies enabled in standby mode, the quiescent
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3mm 3mm 0.75mm 20-Lead QFN Package
current drawn from the battery is only 10A. The LTC3554
family are available in a 3mm 3mm 0.75mm 20-lead
a T
QFN package.
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USB-Based Handheld Products L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and PowerPath, Hot Swap and Bat-Track are trademarks of Linear Technology Corporation.
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Portable Li-Ion/Polymer Based Electronic Devices
All other trademarks are the property of their respective owners. Protected by U.S. Patents,
including 6522118, 6700364, 5481178, 6304066, 6570372, 6580258, 7511390.
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Fitness Computers
*See table on page 2 for available options.
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Low Power Medical Devices
Typical a T
4.35V TO 5.5V SYSTEM
V V
BUS OUT
USB INPUT LOAD
10F 10F
100k
Battery Drain Current
NTC CHRG
LTC3554
vs Temperature
PROG BAT
100k T 14
+
Li-Ion V = 3.8V
BAT
1.87k
BATTERY
STBY = 3.8V
12
REGULATORS LOAD = 0mA
BOTH REGULATORS
HPWR BVIN
10
ENABLED
2.2F
SUSP
8
4.7H
ONE REGULATOR ENABLED
3.3V
PWR_ON1 SW1
6
200mA
2.05M
10pF 10F
BOTH REGULATORS DISABLED
4
FSEL FB1
649k
2
STBY
HARD RESET
PGOOD
10H 0
1.2V
75 50 25 0 25 50 75 100 125
SW2
PWR_ON2
200mA
TEMPERATURE (C)
10pF 332k 10F
PBSTAT
3554 TA01b
FB2
ON
649k
3554 TA01a
ON/OFF
3554123ff
1
BATTERY DRAIN CURRENT (A)
ion pplica
ions pplica
ion uresLTC3554/LTC3554-1/
LTC3554-2/LTC3554-3
a Te Maxi Mu M r a T p in c F T
(Notes 1, 2, 3)
V , V , BVIN TOP VIEW
BUS OUT
t < 1ms and Duty Cycle < 1% ................... 0.3V to 7V
Steady State ............................................ 0.3V to 6V
20 19 18 17 16
NTC
HPWR 1 15
BAT, NTC, CHRG, SUSP, PBSTAT,
CHRG
FSEL 2 14
ON, PGOOD, FB1, FB2 .................................. 0.3V to 6V
21
SW1
PBSTAT 3 13
GND
PWR_ON1, PWR_ON2, STBY
BVIN
PGOOD 4 12
HPWR, FSEL (Note 4) ......................0.3V to V + 0.3V
CC
SW2
ON 5 11
I .............................................................................1A 6 7 8 9 10
BAT
I , I (Continuous) ...................................... 300mA
SW1 SW2
I , I I ............................................75mA
CHRG PGOOD, PBSTAT
Operating Junction Temperature Range ...40C to 85C
UD PACKAGE
20-LEAD (3mm 3mm) PLASTIC QFN
Junction Temperature ............................................110C
T = 110C, = 58.7C/W
JMAX JA
EXPOSED PAD (PIN 21) IS GND, AND MUST BE SOLDERED TO PCB GND
Storage Temperature Range .................. 65C to 125C
o r Der i n F Ma T
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3554EUD#PBF LTC3554EUD#TRPBF LDYS 20-Lead (3mm 3mm) Plastic QFN 40C to 85C
LTC3554EUD-1#PBF LTC3554EUD-1#TRPBF LGFG 20-Lead (3mm 3mm) Plastic QFN 40C to 85C
LTC3554EUD-2#PBF LTC3554EUD-2#TRPBF LFZX 20-Lead (3mm 3mm) Plastic QFN 40C to 85C
LTC3554EUD-3#PBF LTC3554EUD-3#TRPBF LGHK 40C to 85C
20-Lead (3mm 3mm) Plastic QFN
LTC3554EPD#PBF LTC3554EPD#TRPBF FDPT 20-Lead (3mm 3mm) Plastic UTQFN 40C to 85C (OBSOLETE)
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: