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

tuneProduct Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active TDFN Tube 75
Active TDFN Reel 6000


Title language Type Format File Size Date
Datasheets & Errata
star ISL9209C Datasheet Datasheet PDF 981 KB
Application Notes & White Papers
Five Easy Steps to Create a Multi-Load Power Solution White Paper PDF 846 KB
AN1681: Grounding Techniques Application Note PDF 509 KB
AN1684: Nonideality of Ground Application Note PDF 397 KB
PCN20029A - Alternate bond wire material and assembly facility of the listed Renesas QFN packaged products Product Change Notice PDF 327 KB
PCN15046 - Wafer Fabrication Site Change for Listed Intersil Products - Global Foundry P6 Process transfer to Palm Bay - Phase II Product Change Notice PDF 398 KB
PCN10055 - Alternate Bond Wire Material for Assembly of the Listed Intersil DFN/QFN Packaged Products - STATS ChipPAC Malaysia Product Change Notice PDF 248 KB
TB363: Guidelines for Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs) Other PDF 293 KB
TB389: PCB Land Pattern Design and Surface Mount Guidelines for QFN Packages Other PDF 958 KB
TB379: Thermal Characterization of Packaged Semiconductor Devices Other PDF 653 KB