The ISL9211A is an integrated circuit (IC) optimized to provide a redundant safety protection to a Li-ion battery charging system. The IC monitors the input voltage, the battery voltage, and the charge current. When any of the three parameters exceeds its limit, the IC turns off an internal N-channel MOSFET to remove the power from the charging system to the battery. In addition to the above protected parameters, the IC also monitors its own internal temperature and turns off the N-channel MOSFET when the temperature exceeds +150C. Together with the battery charger IC and the protection module in a battery pack, the charging system using the ISL9211A has triple-level protection and is two-fault tolerant.