LT1571

LT1571 Series Constant-Current/ Constant-Voltage Battery Chargers with Preset Voltage and Termination Flag U U FEATURES s Fast Charging of Li-Ion, NiMH and NiCd Batteries s Simple Charge Current Programming Requires Only One Low Cost, 1/32W Resistor s High Efficiency Charger with Up to 1.5A Charge Current s Precision 0.6% Internal Voltage Reference s Preset Battery Voltages: 4.1V, 4.2V, 8.2V, 8.4V s 500kHz or 200kHz Switching Frequency Minimizes Charger Size s Low Reverse Battery Drain Current: 5µA s Flag Indicates Li-Ion Charge Completion s 5% Typical Charge Current Accuracy s Low Shutdown Current s LT1571-1: 200kHz, Adjustable Voltage LT1571-2: 200kHz, Fixed 8.2V or 8.4V LT1571-5: 500kHz, Fixed 4.1V or 4.2V U APPLICATIO S s Cellular Phones, PDAs, Notebook Computers, Portable Instruments s Cradle Chargers for Li-Ion, NiCd, NiMH and Lead-Acid Rechargeable Batteries DESCRIPTIO The LT®1571 PWM battery charger is a simple, efficient solution to fast-charge rechargeable batteries including lithium-ion (Li-Ion), nickel-metal-hydride (NiMH) and nickel-cadmium (NiCd) using constant-current and/or constant-voltage control. The internal switch is capable of delivering 1.5A DC current (2A peak current). The onboard current sense resistor (0.1Ω) allows simple charge current programming to within 5% accuracy using a low cost external resistor. The constant-voltage output can be selected for 4.1V or 4.2V per cell with 0.6% accuracy. LT1571 can charge batteries ranging from 1V to 20V. A...