Single-cell Li Battery Charger For Current-limited Supply Integrated Products

The MAX1679 Battery Charger for a single lithium-ion (Li+) cell comes in a space-saving 8-pin MAX package. This simple device, in conjunction with a current-limited wall cube and a PMOS Transistor allows safe and fast charg- ing of a single Li+ cell. The MAX1679 initiates charging in one of three ways: battery insertion, charger power-up, or external manip- ulation of the THERM pin. Charging terminates when the average charging current falls to approximately 1% of the fast-charge current, or when the on-chip Counter times out. Key safety features include continuous voltage and temperature monitoring, a programmable charger time- out, and a 5mA 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 MAX1679 evaluation kit (MAX1679EVKIT) is avail- able to help reduce design time. By Maxim Integrated Products