MAX1879

19-2061; Rev 0; 5/01 ABLE KIT AVAIL N IO T A U L EVA Simple, Efficient, 1-Cell Li+ Pulse Charger General Description The MAX1879 single-cell lithium-ion (Li+) battery charger utilizes an efficient pulse-charging architecture to minimize power dissipation in portable devices. This architecture combines the efficiency of switch-mode chargers with the simplicity and low cost of linear chargers. This simple device, in conjunction with a current-limited wall cube and a PMOS transistor, allows safe and fast charging of a single Li+ cell. The MAX1879 initiates charging in one of three ways: battery insertion, charger power-up, or toggling the THERM pin. Key safety features include continuous voltage and temperature monitoring, a preset charger time-out, and an 8mA precharge current mode to charge near-dead cells. Automatic detection of input power removal shuts down the device, minimizing current drain from the battery. An overall system accuracy of 0.75% ensures that the cell capacity is fully utilized without cycle life degradation. The MAX1879 is offered in a space-saving 8-pin µMAX package. An evaluation kit (MAX1879EVKIT) is available to help reduce design time. o Simple Design Minimizes Heat o Low Component Count, No Inductor o Battery-Full Indicator o 0.75% Accurate Battery Regulation o 1.5µA (max) Battery Current Drain with Wall Cube Removed o Restart Charging at 4.0V o Continuous Overvoltage and Overtemperature Protection o Safely Precharges Near-Dead Cells o Automatic Po...