What this single-cell charger does
The BQ25619ERTWR is a 1-cell Li-Ion/Polymer battery charger IC from Texas Instruments, controlled over an I²C interface. The supply can go up to 13.5V, which covers typical USB or adapter inputs. The chip integrates fault protection against overcurrent, overtemperature, and overvoltage, and lets you program both the charge current and voltage via I²C.
The BQ25619ERTWR comes in a 24-WFQFN Exposed Pad package, with the supplier device package designated as 24-WQFN (4x4).
Texas Instruments is the sole manufacturer. No official successor or second-source has been announced, so this remains the current production part for the BQ25619 series.