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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

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