LTC4056-4.2_15 Datasheet, PDF (1/16 Pages) Linear Technology – Linear Li-Ion Charger with Termination in ThinSOT

LTC4056-4.2
Linear Li-Ion Charger
with Termination in ThinSOT
FEATURES
s _{Standalone Li-Ion Charger with Termination}
s _{Programmable Termination Timer}
s _{No Sense Resistor or Blocking Diode Required}
s _{Suitable for USB-Powered Charging}
s _{Undervoltage Charge Current Limiting}
s _{Preset Charge Voltage with ±0.6% Accuracy}
s _{Programmable Charge Current: 200mA to 700mA}
s _{Automatic Recharge with Shortened Charge Cycle}
s _{Self-Protection for Overcurrent/Overtemperature}
s _{40µA Supply Current in Shutdown Mode}
s _{Negligible Battery Drain Current in Shutdown}
s _{Low Battery Charge Conditioning (Trickle Charging)}
s _{CHRG Status Output including AC Present}
s _{PCB Total Solution Area only 75mm}² _(700mA)
s _{Low Profile (1mm) SOT-23 Package}
U
APPLICATIO S
s _{Cellular Telephones}
s _{Handheld Computers}
s _{Digital Cameras}
s _{Charging Docks and Cradles}
s _{Low Cost and Small Size Chargers}
DESCRIPTIO
The LTC^®4056 is a low cost, single-cell, constant-current/
constant-voltage Li-Ion battery charger controller with a
programmable termination timer. When combined with a
few external components, the LTC4056 forms a very small
standalone charger for single cell lithium-ion batteries.
Charge current and charge time are set externally with a
single resistor and capacitor, respectively. The LTC4056
charges to a final float voltage accurate to ±0.6%. Manual
shutdown is accomplished by grounding the TIMER/
SHDN pin, while removing input power automatically puts
the LTC4056 into a sleep mode. Both the shutdown and
sleep modes drain near zero current from the battery; the
shutdown mode reduces supply current to 40µA.
The output driver is both current limited and thermally
protected to prevent operating outside of safe limits. No
external blocking diode or sense resistor is required. The
LTC4056 also includes low battery charge conditioning
(trickle charging), undervoltage charge current limiting,
automatic recharge and a charge status output.
The LTC4056 is available in a low profile (1mm) 8-lead
SOT-23 (ThinSOT^TM) package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
V_IN
4.5V TO 6.5V
LTC4056
V_CC
I_SENSE
700mA
CHARGE
CHRG
DRIVE
ZXT1M322
STATUS
TIMER/SHDN BAT
1µF
PROG
1µF
1.3k
GND
+ _1-CELL
4.2V Li-Ion
4056-4.2 TA01
V_IN Undervoltage Charge
Current Limiting
800
V_BAT = 4V
700 ^{RPROG = 1.3k}
I_CHG = 700mA
600 ^{INPUT Z = 100mΩ}
CONSTANT
CURRENT
500 ^{UNDERVOLTAGE CHARGE}
CURRENT LIMITING
400
300
200
UNDERVOLTAGE
100
LOCKOUT
AT 4.35V
0
4.40 4.45 4.50 4.55 4.60 4.65 4.70 4.75
V_IN (V)
4056 TA02
405642f
1