The LTC4006 is a complete constant-current/constant voltage 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 by an external resistor, sets the total charge time or is reset to 25% of total charge time after C/10 charging current is reached. Charging automatically resumes when the cell voltage falls below 3.9V/cell. Fully discharged cells are automatically trickle charged at 10% of the programmed current until the cell voltage exceeds 2.5V/cell. Charging terminates if the low-battery condition persists for more than 25% of the total charge time. The LTC4006 includes a thermistor sensor input that suspends charging if an unsafe temperature condition is detected and automatically resumes charging when the battery temperature returns to within safe limits. Applications * Notebook Computers * Portable Instruments * Battery-Backup Systems * Standalone Li-Ion Chargers * 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 https://elecena.pl/product/260163/4a-high-efficiency-standalone-li-ion-battery-charger 2007-03-04 https://elecena.pl/product/260163/4a-high-efficiency-standalone-li-ion-battery-charger 2014-06-12 https://elecena.pl/product/260163/4a-high-efficiency-standalone-li-ion-battery-charger 2025-01-20