ISL9211B: Charging System Safety Circuit

The ISL9211B is an integrated circuit (IC) optimized to provide a redundant safety protection to a Li-ion battery charging system. The IC monitors input voltage, battery voltage, and charge current. When any of these parameters exceeds its limit, the IC turns off an internal N-channel MOSFET to remove power from the charging system to the battery. The IC also monitors its own internal temperature and turns off the N-channel MOSFET when the temperature exceeds +150°C. Together with the battery charger IC and the protection module in a battery pack, the charging system using the ISL9211B has triple-level protection and is two-fault tolerant.

The IC is designed to turn on the internal NFET slowly, to avoid in-rush current at
power-up. It turns off the NFET quickly when the input is overvoltage, to remove power before damage occurs. The ISL9211B has a logic flag output to indicate a fault condition. The enable input allows the system to cut off the input power, if needed.

Key Features
  • 24V Max Input Voltage
  • Supports Up To 2.0A Input Current
  • Fully Integrated Protection Circuit for Three Protected Variables
  • High Accuracy Protection Thresholds
  • User Programmable Overcurrent Protection Threshold
  • Responds to Input Overvoltage in Less Than 1µs
  • High Immunity of False Triggering Under Transients
  • Fault Indication for Various Fault Occurrence
  • Easy to Use
  • Pb-Free (RoHS Compliant)
Applications
  • Cell Phones
  • Digital Still Cameras
  • PDAs and Smart Phones
  • Portable Instruments
  • Desktop Chargers
Typical Diagram
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL9211B DatasheetPDF20 Nov 2014375 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
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
ISL9211BIRU58XZ-T8 Ld uTDFN T+R0.006081260RoHS
ISL9211B Datasheet 20 Nov 2014
8 Ld uTDFN T+R ISL9211A
ISL9211B
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
Five Easy Steps to Create a Multi-Load Power Solution 30 Jan 2017