LTC4095 Datasheet, PDF (1/16 Pages) Linear Technology – Standalone USB Li-Ion/Polymer Battery Charger in 2mm × 2mm DFN

LTC4095
Standalone USB
Li-Ion/Polymer Battery
Charger in 2mm × 2mm DFN
FEATURES
■ _{Full-Featured Standalone USB Li-Ion/Polymer}
Battery Charger
■ _{100mA to 950mA Programmable Charge Current}
■ _{C/10 Charge Current Detection Output}
■ _{Internal Safety Timer Termination}
■ _{NTC Thermistor Input for Temperature Qualified}
Charging
■ _{Preset 4.2V Float Voltage with 0.5% Accuracy}
■ _{Constant-Current/Constant-Voltage Operation with}
Thermal Feedback
■ _{Charge Current Monitor Output for Gas Gauging}
■ _{Automatic Recharge}
■ _{Bad-Battery Detection}
■ _{8.5µA Input Supply Current in Suspend Mode}
■ _{Tiny 8-Lead (2mm × 2mm) DFN Package}
APPLICATIONS
■ _PDAs
■ _{Media Players}
■ _{Cellular Phones}
■ _{Other Portable Electronics}
DESCRIPTION
The LTC^®4095 is a complete constant-current/constant-
voltage linear charger for single-cell lithium-ion/polymer
batteries. Its small 2mm × 2mm DFN package and low
external component count make the LTC4095 especially
well-suited for portable USB power applications.
Up to 950mA of charge current may be programmed via a
single resistor from the PROG pin to ground. The HPWR
pin allows the charge current to be set at 20% or 100% of
its full-scale programmed value. An internal safety timer
terminates charge current. The final float voltage is preset
to 4.2V and held to a tight 0.5% tolerance. Also featured
is an NTC thermistor input to monitor battery temperature
while charging, a C/10 current detection output, automatic
recharge, bad-battery detection and low-battery trickle
charge. A thermal feedback loop regulates the charge
current to limit the die temperature during high power
operation or high ambient thermal conditions.
The LTC4095 is available in a tiny, low profile (0.75mm)
8-lead 2mm × 2mm DFN package.
, 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, 6570372, 6700364.
TYPICAL APPLICATION
500mA Single-Cell Li-Ion Charger
IN
4.3V TO 5.5V
UP TO 7V
TRANSIENTS
C_IN
1µF
IN
BAT
LTC4095
HPWR CHRG
SUSP NTC
PROG
GND
+ _Li-Ion
BATTERY
R_PROG
1.74k
4095 TA01a
4095fa
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