LTC4061 Datasheet, PDF (1/20 Pages) Linear Technology – Standalone Linear Li-lon Battery Charger with Thermistor Input

FEATURES
■ _{Charge Current Programmable up to 1A}
■ _{Charges Single Cell Li-Ion Batteries Directly from}
USB Port
■ _{Preset Charge Voltage with ±0.35% Accuracy}
■ _{Thermistor Input for Temperature Qualified}
Charging
■ _{Input Supply Present Logic Output}
■ _{Thermal Regulation Maximizes Charge Rate}
Without Risk of Overheating*
■ _{Programmable Charge Current Detection/}
Termination
■ _{Programmable Charge Termination Timer}
■ _{Smart Pulsing Error Feature}
■ _SmartStart^TM _{Prolongs Battery Life}
■ _{20µA Charger Quiescent Current in Shutdown}
■ _{Available in a Low Profile (0.75mm) 10-Lead}
(3mm × 3mm) DFN Package
U
APPLICATIO S
■ _{Handheld Computers}
■ _{Portable MP3 Players}
■ _{Digital Cameras}
LTC4061
Standalone Linear Li-Ion Battery
Charger with Thermistor Input
DESCRIPTIO
The LTC^®4061 is a full-featured, flexible, standalone linear
charger for single-cell Lithium-Ion batteries. It is capable
of operating within USB power specifications.
Both programmable time and programmable current
based termination schemes are available. Furthermore,
the ^⎯C^⎯H^⎯R^⎯G open-drain status pin can be programmed to
indicate the battery charge state according to the needs
of the application. Additional safety features designed to
maximize battery lifetime and reliability include NTC bat-
tery temperature sensing and the SmartStart^TM charging
algorithm.
No external sense resistor or external blocking diode is
required for charging due to the internal MOSFET archi-
tecture. Internal thermal feedback regulates the charge
current to maintain a constant die temperature during
high power operation or high ambient temperature condi-
tions. The charge current is programmed with an external
resistor. With power applied, the LTC4061 can be put into
shutdown mode to reduce the supply current to 20µA and
the battery drain current to less than 2µA.
Other features include smart recharge, USB ^⎯C^⎯/^⎯5 cur-
rent programming input, undervoltage lockout and AC
Present logic.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
SmartStart is a trademark of Linear Technology Corporation.
*Protected by U.S. Patents including 6522118.
TYPICAL APPLICATIO
800mA Single Cell Li-Ion Battery Charger
(C/10 Termination)
V_IN
4.3V TO 8V
1µF
619Ω
V_CC
BAT
EN LTC4061
C/5
CHRG
TIMER ACPR
PROG
I_DET
NTC
GND
800mA
+ ^4.2V
SINGLE CELL
Li-Ion BATTERY
4061 TA01a
Complete Charge Cycle (1100mAh Battery)
900
4.3
800
4.2
700
4.1
600
4.0
500
3.9
400
BATTERY
VOLTAGE
BATTERY
CURRENT
3.8
300
3.7
200
100 ^VCC ^{= 5V}
T_A = 25°C
0
0 0.5 1.0 1.5 2.0
TIME (HOURS)
3.6
3.5
3.4
2.5 3.0
4061 TA01b
4061fa
1