Highly Integrated Battery Charger with Automatic Power Source Selector for Notebook Computers

The ISL6256, ISL6256A is a highlyintegrated 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.

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

• Programmable Charge Current Limit, Adapter Current

Limit and Charge Voltage

• Fixed 300kHz PWM Synchronous Buck Controller with

Diode Emulation at Light Load

• Overvoltage Protection

• 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

• Supports Pulse Charging

• Pb-Free Plus Anneal Available (RoHS Compliant)

Applications

• Notebook, Desknote and Sub-notebook Computers

• Personal Digital Assistant