The ISL6252, ISL6252A is a highly integrated battery charger
controller for Li-ion/Li-ion polymer batteries. High Efficiency is
achieved by a synchronous buck topology. 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 ISL6252, ISL6252A provides outputs
that are used to monitor the current drawn from the AC
adapter, and monitor for the presence of an AC adapter. The
ISL6252, ISL6252A automatically transitions from regulating
current mode to regulating voltage mode.