The ISL6255, ISL6255A is a highly integrated battery charger
controller for Li-Ion/Li-Ion 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 and 4
series Li-Ion cells with 0.5% accuracy over temperature. It can
also be programmed between 4.2V+5%/cell and 4.2V-5%/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 a wide range of programmable charging current. The
ISL6255, ISL6255A provides outputs that are used to monitor
the current drawn from the AC adapter, and monitor for the
presence of an AC adapter. The ISL6255, ISL6255A
automatically transitions from regulating current mode to
regulating voltage mode.
ISL6255, ISL6255A has a feature for 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 provides a DC adapter monitor to support
aircraft power applications with the option of no battery
charging.

Features
• ±0.5% Charge Voltage Accuracy (-10°C to 100°C)
• ±3% Accurate Input Current Limit
• ±3% Accurate Battery Charge Current Limit
• ±25% Accurate Battery Trickle Charge Current Limit
(ISL6255A)
• Programmable Charge Current Limit, Adapter Current
Limit and Charge Voltage
• Fixed 300kHz PWM Synchronous Buck Controller with
Diode Emulation at Light Load
• Output for Current Drawn from AC Adapter
• AC Adapter Present Indicator
• Fast Input Current Limit Response
• Input Voltage Range 7V to 25V
• Support 2, 3 and 4 Cells Battery Pack
• Up to 17.64V Battery-Voltage Set Point
• 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
• Support Pulse Charging
• Charge Any Battery Chemistry: Li-Ion, NiCd, NiMH, etc.
• Pb-Free Plus Anneal Available (RoHS Compliant)

Applications
• Notebook, Desknote and Sub-notebook Computers
• Personal Digital Assistant