2 A single-cell Li-Ion charger with I²C current control
The Texas Instruments BQ24250RGET is a single-cell Lithium-Ion battery charger that draws up to 2 A charging current from an input supply rated to 10.5 V max. It uses an I²C interface to program the charge current, so the host MCU can adjust the rate without swapping a set-resistor — useful when the same board must charge from USB, a 5 V wall adapter, or a 9 V supply.
Why the 2 A ceiling and 10.5 V input matter on the BOM
The 2 A max charge current sets the thermal budget for the 24-VQFN (4x4 mm) exposed-pad package. At full current the die-to-ambient temperature rise depends on the PCB copper area under the pad — a 2-layer board with a 1-inch² pour keeps the junction below the 125°C limit; a tight layout needs a thermal via array to the ground plane. The 10.5 V input ceiling covers 5 V USB and 9 V quick-charge adapters but not 12 V rails — a 12 V input exceeds the abs-max and kills the part on first plug-in. Fault protection is on-die: over-current, over-temperature, and over-voltage shut down the pass FET without an external fuse or supervisor. That saves a PTC and a comparator on the BOM — worth factoring into the board-area budget.