
LTC4061
1
4061fa
FEATURES
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.
U
APPLICATIU
■
Handheld Computers
■
Portable MP3 Players
■
Digital Cameras
TYPICAL APPLICATIO
800mA Single Cell Li-Ion Battery Charger
(C/10 Termination)
U
+
V
CC
EN
TIMER
PROG
I
DET
BAT
CHRG
ACPR
NTC
LTC4061
GND
800mA
619
1μF
V
IN
4.3V TO 8V
4061 TA01a
4.2V
SINGLE CELL
Li-Ion BATTERY
C/5
TIME (HOURS)
0
0.5
1.5
2.5
3.0
C
B
2.0
900
800
700
600
500
400
300
200
100
0
4.3
4.2
4.1
4.0
3.9
3.8
3.7
3.6
3.5
3.4
4061 TA01b
1.0
BATTERY
CURRENT
BATTERY
VOLTAGE
V
CC
= 5V
T
A
= 25°C
■
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
Standalone Linear Li-Ion Battery
Charger with Thermistor Input
Complete Charge Cycle (1100mAh Battery)
SmartStart is a trademark of Linear Technology Corporation.
*Protected by U.S. Patents including 6522118.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.