DATASHEET
ISL9211A
Charging System Safety Circuit
FN6702
Rev 3.00
November 5, 2014
The ISL9211A is an integrated circuit (IC) optimized to provide
a redundant safety protection to a Li-ion battery 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 N-channel MOSFET
to remove the power from the charging system to the battery.
In addition to the above protected parameters, 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 ISL9211A has
triple-level protection and is two-fault tolerant.
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
The IC is designed to turn on the internal NFET slowly to avoid
inrush current at power up but will turn off the NFET quickly
when the input is overvoltage in order to remove the power
before any damage occurs. The ISL9211A has a logic flag
output to indicate a fault condition. The enable input allows
the system to cut off the input power if needed.
• Pb-Free (RoHS Compliant)
Applications
• Cell Phones
Related Literature
• Digital Still Cameras
• PDAs and Smart Phones
• Portable Instruments
• Desktop Chargers
• Technical Brief TB363 “Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
(SMDs)”
• Technical Brief TB379 “Thermal Characterization of
Packaged Semiconductor Devices”
• Technical Brief TB389 “PCB Land Pattern Design and
Surface Mount Guidelines for QFN Packages”
INPUT
VIN
OUT
ISL6292
BATTERY
CHARGER
C1
C2
ISL9211A
RVB
VB
EN
ILIM
DISA
ENA
RILIM
BATT
PACK
GND
FAULT
FIGURE 1. TYPICAL APPLICATION CIRCUIT
FN6702 Rev 3.00
November 5, 2014
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