The ISL9209C is an integrated circuit (IC) optimized to provide a redundant safety protection to a Li-ion battery from failures of a 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 P-Channel MOSFET to remove the power from the charging system. In addition to the above protected parameters, the IC also monitors its own internal temperature and turns off the P-Channel MOSFET when the temperature exceeds +140°C. Together with the battery charger IC and the protection module in a battery pack, the charging system using the ISL9209C has triple-level protection and is two-fault tolerant.

The IC is designed to turn on the internal PFET slowly to avoid in-rush current at power-up but will turn off the PFET quickly when the input is overvoltage in order to remove the power before any damage occurs. The ISL9209C has a logic warning output to indicate the fault and an enable input to allow the system to remove the input power.

• Fully Integrated Protection Circuit for Three Protected Variables
• High Accuracy Protection Thresholds
• User Programmable Overcurrent Protection Threshold
• Input Overvoltage Protection in Less Than 1μs
• High Immunity of False Triggering Under Transients
• Warning Output to Indicate the Occurrence of Faults
• Enable Input
• Easy to Use
• Thermal Enhanced TDFN Package
• Pb-Free (RoHS Compliant)

• Cell Phones
• Digital Still Cameras
• PDAs and Smart Phones
• Portable Instruments
• Desktop Chargers