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ISL6253
Highly Integrated Battery Charger for
Notebook Computers
The ISL6253 is a highly integrated battery charger controller
for Li-Ion/Li-Polymer batteries. High Efficiency is achieved by
a synchronous buck topology and the use of a MOSFET,
instead of a diode, for selecting power from the adapter or
battery. The low side MOSFET emulates a diode at light
loads to improve the light load efficiency and prevent system
bus boosting.
The constant output voltage can be selected for 2, 3 or 4
series Li-Ion cells with 0.5% accuracy over temperature. It
can also be programmed between 4.2V +5% per cell and
4.2V -5% per cell to optimize battery capacity. When
supplying the load and battery charger simultaneously, the
input current limit for the AC adapter is programmable to
within 3% accuracy to avoid overloading the AC adapter,
and to allow the system to make efficient use of available
adapter power for charging. It also has programmable
charging current with 4% accuracy. The ISL6253 provides
outputs that are used to monitor the current drawn from the
AC adapter, and to monitor for the presence of an AC
adapter. The ISL6253 automatically transitions from
regulating current to regulating voltage. A conditioning
charge feature provides approximately 10% of full scale
charge current to safely charge deeply discharged lithium-
ion (LI+) battery packs when the battery voltage is below
3.0V/cell.
ISL6253 has a feature of automatic power source selection
by switching to the battery when the AC adapter is removed
or switching to the AC adapter when the AC adapter is
available. It also supports aircraft power applications while
powering the system and not charging the battery.
Features
±0.5% Voltage Accuracy
±3% Input Current Limit Accuracy
±4% Accurate Battery Charge Current Limit
Programmable Charge Limit Current, Adaptor Current
Limit and Charge Voltage
Fixed 300kHz PWM Synchronous Buck Controller with
Diode Emulation at Light Load
Output for Current Drawn from the AC Adapter
AC Adapter Present Indicator
Fast Input Current Limit Response
Input Voltage Range 7V to 25V
Up to 17.6V Battery-Voltage Set Point
Trickle Charge Mode When Battery Voltage is below
3.0V/Cell
Supports 2, 3 and 4 Cell Battery Packs
Control Adapter Power Source Select MOSFET
Thermal Shutdown
Aircraft Power Capable
DC Adapter Present Indicator
Battery Discharge MOSFET Control
Less than 10μA Battery Leakage Current
QFN Package
- Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat
No Leads - Package Outline
- Near Chip Scale Package footprint, which improves
PCB efficiency and has a thinner profile
Pb-free Available
Applications
Notebook, Desknote and Sub-notebook Computers
Personal Digital Assistants
Ordering Information
PART #
TEMP.
RANGE (°C)
PACKAGE
PKG.
DWG. #
ISL6253HRZ
(Note 1)
-10 to 100
28 Ld 5x5 QFN
(Pb-free)
L28.5x5
ISL6253HAZ
(Note 1)
-10 to 100
28 Ld QSOP
(Pb-free)
M28.15
NOTES:
1. Intersil Pb-free products employ special Pb-free material sets;
molding compounds/die attach materials and 100% matte tin
plate termination finish, which is compatible with both SnPb and
Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or
exceed the Pb-free requirements of IPC/JEDEC J Std-020B.
2. Add “-T” for Tape and Reel.
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2004. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
Data Sheet
August 2004
FN9117.2