ISL9212A
Charging System Safety Circuit
Typical Diagram
Key Features
- Fully Integrated Protection Circuit for Three Protection Variables
- User Programmable Overcurrent Protection Threshold
- Input Overvoltage Protection in Less Than 1µs
- Battery Overvoltage Protection
- High Immunity of False Triggering Under Transients
- High Accuracy Protection Thresholds
- Warning Output to Indicate the Occurrence of Faults
- Enable Input
- Thermal Enhanced DFN Package
- Pb-Free Plus Anneal Available (RoHS Compliant)
Description
The ISL9212A is an integrated circuit (IC) optimized to provide a Li-ion battery redundant safety protection 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 die temperature exceeds +140°C. Together with the battery charger IC and the protection module in a battery pack, the charging system using the ISL9212A has triple-level protection and is two-fault tolerant.
The IC is designed to turn on the internal PFET slowly to avoid inrush current at power-up but will turn off the PFET quickly when input overvoltage is detected, in order to remove the power before any damage occurs. The ISL9212A has a logic warning output to indicate the fault and an enable input to allow the system to remove the input power.
Applications
- Cell Phones
- Digital Still Cameras
- PDAs and Smart Phones
- Portable Instruments
- Desktop Chargers
