LTC4009
LTC4009-1/LTC4009-2
High Efficiency,
Multi-Chemistry
Battery Charger
Description Features
General Purpose Battery Charger Controller
Efficient 550kHz Synchronous Buck PWM Topology
±0.5% Output Float Voltage Accuracy
Programmable Charge Current: 4% Accuracy
Programmable AC Adapter Current Limit:
3% Accuracy
No Audible Noise with Ceramic Capacitors
Wide Input Voltage Range: 6V to 28V
Wide Output Voltage Range: 2V to 28V
Indicator Outputs for AC Adapter Present, Charging,
C/10 Current Detection and Input Current Limiting
n Analog Charge Current Monitor
n Micropower Shutdow Thermally Enhanced 20-Pin 4mm × 4mm × 0.75mm
QFN Package n n n n n n n n n Applications Notebook Computers Portable Instruments
n Battery Backup Systems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners. Protected by U.S. Patents including 5723970. The LTC®4009 is a constant-current/constant-voltage …