LTC4006

U U LTC4006 4A, High Efficiency, Standalone Li-Ion Battery Charger FEATURES DESCRIPTIO ■ Complete Charger Controller for 2-, 3- or 4-Cell Lithium-Ion Batteries ■ High Conversion Efficiency: Up to 96% ■ Output Currents Exceeding 4A ■ ±0.8% Accurate Preset Voltages: 8.4V, 12.6V, 16.8V ■ Built-In Charge Termination with Automatic Restart ■ AC Adapter Current Limiting Maximizes Charge Rate* ■ Automatic Conditioning of Deeply Discharged Batteries ■ Thermistor Input for Temperature Qualified Charging ■ Wide Input Voltage Range: 6V to 28V ■ 0.5V Dropout Voltage; Maximum Duty Cycle: 98% ■ Programmable Charge Current: ±4% Accuracy ■ Indicator Outputs for Charging, C/10 Current Detection and AC Adapter Present ■ Charging Current Monitor Output ■ 16-Pin Narrow SSOP Package U APPLICATIO S ■ Notebook Computers ■ Portable Instruments ■ Battery-Backup Systems ■ Standalone Li-Ion Chargers The LTC®4006 is a complete constant-current/constantvoltage charger controller for 2-, 3- or 4-cell lithium batteries in a small package using few external components. The PWM controller is a synchronous, quasi-constant frequency, constant off-time architecture that will not generate audible noise even when using ceramic capacitors. The LTC4006 is available in 8.4V, 12.6V and 16.8V versions with±0.8% voltage accuracy. Charging current is programmable with a single sense resistor to ±4% typical accuracy. Charging current can be monitored as a representative voltage at the IMON pin. A timer, programmed ...