DESCRIPTION
The LTC®1731-8.2/LTC1731-8.4 are complete constantcurrent/constant-voltage linear charger controllers for 2-cell lithium-ion (Li-Ion)batteries. Nickel-cadmium (NiCd) and nickel-metal-hydride (NiMH) batteries can also be charged with constant current using external termination. The external sense resistor sets the charge current with 7% accuracy. An internal resistor divider and precision reference set the final float potential with 1% accuracy. The output float voltages are set internally to 8.2V (LTC1731-8.2) or 8.4V (LTC1731-8.4).

FEATURES
■ Complete Linear Charger Controller for 2-Cell Lithium-Ion Batteries
■ 1% Voltage Accuracy
■ Programmable Charge Current
■ C/10 Charge Current Detection Output
■ Programmable Charge Termination Timer
■ Space Saving 8-Pin MSOP Package
■ Automatic Sleep Mode When Input Supply is Removed (15µA Battery Drain)
■ Automatic Trickle Charging of Low Voltage Cells
■ Programmable for Constant-Current-Only Mode

APPLICATIONS
■ Cellular Phones
■ Handheld Computers
■ Charging Docks and Cradles
■ Programmable Current Source