ISL9209B: Charging System Safety Circuit

The ISL9209B 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 ISL9209B 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 the input is overvoltage in order to remove the power before any damage occurs. The ISL9209B has a logic warning output to indicate the fault and an enable input to allow the system to remove the input power.

Key Features
  • 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 Plus Anneal Available (RoHS Compliant)
Applications
  • Cell Phones
  • Digital Still Cameras
  • PDAs and Smart Phones
  • Portable Instruments
  • Desktop Chargers
Typical Diagram
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL9209B DatasheetPDF17 Nov 2014596 KB
Tech Briefs
TitleTypeUpdatedSizeOther Languages
TB379: Thermal Characterization of Packages for ICsPDF10 Aug 2015282 KB
TB363: Guidelines for Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs)PDF13 Jan 201529 KB
TB389: PCB Land Pattern and Surface Mount Guidelines for QFN PackagesPDF19 Nov 2014661 KB
User Guides
TitleTypeUpdatedSizeOther Languages
ISL9209EVAL1Z User GuidePDF13 Nov 20141.1 MB
White Papers
TitleTypeUpdatedSizeOther Languages
Five Easy Steps to Create a Multi-Load Power SolutionPDF30 Jan 2017502 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ISL9209BIRZ12 Ld DFN0.0285123260RoHS
ISL9209BIRZ-T12 Ld DFN T+R0.0285123260RoHS
ISL9209B Datasheet 17 Nov 2014
12 Ld DFN T+R ISL9212
ISL9209B
TB379: Thermal Characterization of Packages for ICs 10 Aug 2015
TB363: Guidelines for Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs) 13 Jan 2015
TB389: PCB Land Pattern and Surface Mount Guidelines for QFN Packages 19 Nov 2014
ISL9209EVAL1Z User Guide 13 Nov 2014
Five Easy Steps to Create a Multi-Load Power Solution 30 Jan 2017