The LTC4069EDC-4.4#PBF is a complete constant-current/constant-voltage Linear Charger for high capacity single-cell Li-ion batteries with a 4.4V float voltage. It is specifically designed to work within USB power specifications. The CHRG pin indicates when charge current has dropped to ten percent of its programmed value (C/10). An internal timer terminates charging according to battery manufacturer specifications. No external sense resistor or blocking diode is required due to the internal MOSFET architecture. Thermal feedback regulates charge current to limit the die temperature during high power operation or high ambient temperature conditions. When the input supply (wall adapter or USB supply) is removed, the LTC4069-4.4 automatically enters a low current state, dropping battery drain current to less than 1μA. With power applied, it can be put into shutdown mode, reducing the supply current to less than 20μA.
C/10 charge current detection output
Timer charge termination
Charge current programmable up to 750mA with 5% accuracy
No external MOSFET, sense resistor or blocking diode required
NTC thermistor input for temperature qualified charging
Preset 4.4V float voltage with 0.6% accuracy
Charge current monitor output for gas gauging
Automatic recharge
Charges single-cell Li-ion batteries directly from USB port
