LTC4075HVX Datasheet, PDF (1/16 Pages) Linear Technology – High Voltage Dual Input Li-Ion/Polymer Battery Charger

FEATURES
■ _{22V Maximum Voltage for Wall Adapter and}
USB Inputs
■ _{Charge Single-Cell Li-Ion Batteries from Wall}
Adapter and USB Inputs
■ _{Automatic Input Power Detection and Selection}
■ _{Charge Current Programmable up to 950mA from}
Wall Adapter Input
■ _{Overvoltage Lockout for Wall Adapter and}
USB Inputs
■ _{No External MOSFET, Sense Resistor or Blocking}
Diode Needed
■ _{Thermal Regulation Maximizes Charge Rate Without}
Risk of Overheating*
■ _{Preset Charge Voltage with ±0.35% Accuracy}
■ _{Programmable Charge Current Termination}
■ _{40μA USB Suspend Current in Shutdown}
■ _{Independent “Power Present” Status Outputs}
■ _{Charge Status Output}
■ _{Automatic Recharge}
■ _{Available in a Thermally Enhanced, Low Profile}
(0.75mm) 10-Lead (3mm × 3mm) DFN Package
APPLICATIONS
■ _{Cellular Telephones}
■ _{Handheld Computers}
■ _{Portable MP3 Players}
■ _{Digital Cameras}
LTC4075HVX
High Voltage Dual Input
Li-Ion/Polymer Battery
Charger
DESCRIPTION
The LTC^®4075HVX is a standalone linear charger that is
capable of charging a single-cell Li-Ion/Polymer battery
from both wall adapter and USB inputs. The charger can
detect power at the inputs and automatically select the
appropriate power source for charging.
No external sense resistor or blocking diode is required
for charging due to the internal MOSFET architecture. The
LTC4075HVX features a maximum 22V rating for both
wall adapter and USB inputs although charging stops if
the selected power source exceeds the overvoltage limit.
Internal thermal feedback regulates the battery charge
current to maintain a constant die temperature during high
power operation or high ambient temperature conditions.
The float voltage is fixed at 4.2V and the charge current is
programmed with an external resistor. The LTC4075HVX
terminates the charge cycle when the charge current drops
below the programmed termination threshold after the
final float voltage is reached.
Other features include automatic recharge, undervoltage
lockout, charge status outputs, and “power present” status
outputs to indicate the presence of wall adapter or USB
power. No trickle charge allows full current from the charger
when a load is connected directly to the battery.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All
other trademarks are the property of their respective owners.
*Protected by U.S. Patents including 6522118, 6700364.
TYPICAL APPLICATION
Dual Input Battery Charger for Single-Cell Li-Ion
WALL
ADAPTER
USB
PORT
1μF
LTC4075HVX
DCIN
BAT
USBIN
1μF
IUSB
2k
IDC
ITERM
1% _1.24k
GND
1%
800mA (WALL)
500mA (USB)
+ ^4.2V
SINGLE CELL
Li-Ion BATTERY
2k
1%
4075hvx TA01
Charge Current vs Supply Voltage
900
R_IDC = 1.24k
800
R_IUSB = 2k
V_BAT = 3.5V
700
CHARGE FROM DCIN
600
500
400
CHARGE
300
FROM USBIN
200
100
0
2 3 4 5 6 7 8 19 20
SUPPLY VOLTAGE (V)
4075hvx TA01b
4075hvxf
1