The ISL6294A 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
7.3V, to prevent excessive power dissipation. The 28V rating
eliminates the overvoltage protection circuit required in a low
input voltage charger.
The charge current and the end-of-charge (EOC) current are
programmable with external resistors. When the battery
voltage is lower than typically 2.55V, the charger
preconditions the battery with typically 20% of the
programmed charge current. When the charge current
reduces to the programmable EOC current level during the
CV charge phase, an EOC indication is provided by the CHG
pin, which is an open-drain output. An internal thermal
foldback function protects the charger from any thermal
failure.
Two indication pins (PPR and CHG) allow simple interface to
a microprocessor or LEDs. When no adapter is attached or
when disabled, the charger draws less than 1μA leakage
current from the battery.