The ISL9222A is a cost-effective, fully integrated high input
voltage single-cell Li-ion battery charger. The charger uses a
CC/CV charge profile required by Li-ion batteries. The
charger accepts an input voltage up to 28V but is disabled
when the input voltage exceeds the OVP threshold, typically
7.2V, to prevent excessive power dissipation. The 28V rating
eliminates the overvoltage protection circuit required in a low
input voltage charger.
The charge current is user programmable with an external
resistor. When the battery voltage is lower than typically
2.55V, the charger preconditions the battery with typically
20% of the programmed charge current. An internal thermal
foldback function protects the charger from any thermal
failure.
AN indication pin PPR allows simple interface to a
microprocessor or LED. When no adapter is attached or
when disabled, the charger draws less than 1μA leakage
current from the battery.