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LTC4155_15 Datasheet, PDF (1/52 Pages) Linear Technology – Dual-Input Power Manager/ 3.5A Li-Ion Battery Charger with I2C Control and USB OTG
LTC4155
Dual-Input Power Manager/
3.5A Li-Ion Battery Charger with
I2C Control and USB OTG
FEATURES
n High Efficiency Charger Capable of 3.5A
Charge Current
n Monolithic Switching Regulator Makes Optimal
Use of Limited Power and Thermal Budget
n Dual-Input Overvoltage Protection Controller
n Priority Multiplexing for Multiple Inputs
n I2C/SMBus Control and Status Feedback
n NTC Thermistor ADC for Temperature Dependent
Charge Algorithms (JEITA)
n Instant-On Operation with Low Battery
n Battery Ideal Diode Controller for Power
Management
n USB On-The-Go Power Delivery to the USB Port
n Full Featured Li-Ion/Polymer Battery Charger with
Four Float Voltage Settings
n 28-Lead 4mm × 5mm QFN Package
APPLICATIONS
n Tablet PCs
n Ultra Mobile PCs
n Video Media Players
n Digital Cameras, GPS, PDAs
n Smart Phones
n Portable Medical Devices
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and Bat-Track are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
DESCRIPTION
The LTC®4155 is a 15 watt I2C controlled power manager
with PowerPath™ instant-on operation, high efficiency
switching battery charging and USB compatibility. The
LTC4155 seamlessly manages power distribution from
two 5V sources, such as a USB port and a wall adapter,
to a single-cell rechargeable Lithium-Ion/Polymer battery
and a system load.
The LTC4155’s switching battery charger automatically
limits its input current for USB compatibility, or may
draw up to 3A from a high power wall adapter. The high
efficiency step-down switching charger is designed to
provide maximum power to the application and reduced
heat in high power density applications.
I2C adjustability of input current, charge current, battery
float voltage, charge termination, and many other param-
eters allows maximum flexibility. I2C status reporting of
key system and charge parameters facilitates intelligent
control decisions. USB On-The-Go support provides 5V
power back to the USB port without any additional com-
ponents. A dual-input, priority multiplexing, overvoltage
protection circuit guards the LTC4155 from high voltage
damage on the VBUS pin.
The LTC4155 is available in the low profile (0.75mm)
28-lead 4mm × 5mm QFN surface mount package.
TYPICAL APPLICATION
I2C Controlled High Power Battery Charger/USB Power Manager
WALLSNS
WALLGT
1μH
SW
VOUT
TO
SYSTEM
LOAD
VIN
VBUS
10μF
CHGSNS
LTC4155
BATGATE
22μF
USBGT
BATSNS
3.6k
100k
USBSNS
NTCBIAS
ID
NTC
3 I2C IRQ GND CLPROG2 CLPROG1 PROG VC OVGCAP
1.21k 499Ω
47nF
4155 TA01a
Switching Regulator Efficiency
100
90
80
70
60
50
40
30
20
10
VBAT = 3.9V
0
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
LOAD CURRENT (A)
4155 TA01b
4155fc
1