The KF5056 is a complete constant current & constant voltage linear charger for single cell lithium-ion batteries. Its SOP/MSOP package and low external component count make the KF5056 ideally suited for portable applications. Furthermore, the KF5056 is specifically designed to work within USB power specifications. No external sense resistor is needed, and no blocking diode is required due to the internal MOSFET architecture. Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient temperature. The charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The KF5056 automatically terminates the charge cycle when the charge current drops to 1/10 the programmed value after the final float voltage is reached.
When the input supply (wall adapter or USB supply) is removed, the KF5056 automatically enters a low current state, dropping the battery drain current to less than 2uA. The KF5056 can be put into shutdown mode, reducing the supply current to 50uA.
Other features include Battery temperature monitor,under-voltage lockout, automatic recharge and two status pins to indicate charge and charge termination.
Features
Programmable Charge Current Up to 1000mA
No MOSFET, Sense Resistor or Blocking Diode Required
Complete Linear Charger in SOP/MSOP Package for single Cell Lithium-lon Batteries
Constant-Current/Constant- Voltage Operation with
Thermal Regulation to Maximize Charge Rate
Without Risk of Overheating
Charges Single Cell Li-Ion Batteries Directly from USB Port
Preset 4.2V Charge Voltage with土1% Accuracy
Charge Current Monitor Output for Gas Gauging
Automatic Recharge
Charge state pairs of output, no battery and fault
status display
C/10 Charge Termination
50uA Supply Current in Shutdown
2.9V Trickle Charge Threshold
Soft- Start Limits Inrush Current
Battery temperature monitoring function
Available in SOP8-PP/ MSOP8-PP Package
Application
Cellular Telephones, PDAs, MP3 /MP4 Players .
Charging Docks and Cradles
Bluetooth、GPS Applications