ISL88731A: SMBus Level 2 Battery Charger

The ISL88731A is a highly integrated Lithium-ion battery charger controller, programmable over the SMBus system management bus (SMBus). The ISL88731A is intended to be used in a smart battery charger (SBC) within a smart battery system (SBS) that throttles the charge power such that the current from the AC-adapter is automatically limited. High efficiency is achieved with a DC/DC synchronous-rectifier buck converter, equipped with diode emulation for enhanced light load efficiency and system bus boosting prevention. The ISL88731A charges one to four Lithium-ion series cells, and delivers up to 8A charge current. Integrated MOSFET drivers and bootstrap diode result in fewer components and smaller implementation area. Low offset
current-sense amplifiers provide high accuracy with 10mΩ sense resistors. The ISL88731A provides 0.5% end-of-charge battery voltage accuracy.

The ISL88731A provides a digital output that indicates the presence of the AC-adapter as well as an analog output which indicates the adapter current within 4% accuracy.

The ISL88731A is available in a small 5mmx5mm 28 Ld thin (0.8mm) QFN package. An evaluation kit is available to reduce design time. The ISL88731A is available in Pb-Free packages.

Key Features
  • 0.5% Battery Voltage Accuracy
  • 3% Adapter Current Limit Accuracy
  • 3% Charge Current Accuracy
  • SMBus 2 Wire Serial Interface
  • Battery Short Circuit Protection
  • Fast Response for Pulse-Charging
  • Fast System-Load Transient Response
  • Monitor Outputs
    • Adapter Current (3% Accuracy)
    • AC-Adapter Detection
  • 11-Bit Battery Voltage Setting
  • 6 Bit Charge Current/Adapter Current Setting
  • 8A Maximum Battery Charger Current
  • 11A Maximum Adapter Current
  • +8V to +28V Adapter Voltage Range
  • Pb-Free (RoHS compliant)
Applications
  • Notebook Computers
  • Tablet PCs
  • Portable Equipment with Rechargeable Batteries
Typical Diagram
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL88731A DatasheetPDF17 Nov 2014766 KB
Software
TitleTypeUpdatedSizeOther Languages
ISL88731xEVAL2Z Software InstructionsPDF30 Jan 20153.22 MB
ISL88731xEVAL2Z Software Installer v3ZIP11 Nov 201438.86 MB
User Guides
TitleTypeUpdatedSizeOther Languages
ISL88731EVAL2Z, ISL88731CEVAL2Z User GuidePDF13 Nov 2014769 KB
White Papers
TitleTypeUpdatedSizeOther Languages
Five Easy Steps to Create a Multi-Load Power SolutionPDF30 Jan 2017502 KB
Miscellaneous
TitleTypeUpdatedSizeOther Languages
ISL88731 Loop Gain CalculatorXLS19 Dec 2014868 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ISL88731AHRZ28 Ld TQFN0.07283260RoHS
ISL88731AHRZ-T28 Ld TQFN T+R0.07283260RoHS
ISL88731A Datasheet 17 Nov 2014
28 Ld TQFN T+R ISL88550A
ISL88731A
ISL88731xEVAL2Z Software Instructions 30 Jan 2015
ISL88731xEVAL2Z Software Installer v3 11 Nov 2014
ISL88731EVAL2Z, ISL88731CEVAL2Z User Guide 13 Nov 2014
Five Easy Steps to Create a Multi-Load Power Solution 30 Jan 2017
ISL88731 Loop Gain Calculator 19 Dec 2014