Lithium-Ion Battery Pulse Chargers with Overcurrent Protection Features: Complete Pulse Charger for 1-Cell Lithium-Ion Batteries Sense Resistor Limits Maximum Current for Safety 1% Float Voltage Accuracy End-of-Charge (C/10) Detection Output Programmable Charge Termination Timer Internal 0.35 NMOS Switch No Blocking Diode Required SEL Pin to Set Either 4.1V or 4.2V/Cell (LTC1730-4) Low-Battery Drain (1µA Max) when Input Supply Is Removed Battery Temperature Sensing and Charge Qualification Automatic Trickle Charge for Low-Battery Cell Automatic Battery Refresh