8.064 A max charge current — sizing the power path
The BQ24745RHDTG4 is a multi-chemistry battery charger IC from Texas Instruments that handles 2 to 4 series cells with a programmable constant-current charge up to 8.064 A. That current ceiling is the main event for the power-stage design: the inductor, sense resistor, and input capacitor all need to be sized for that peak, not the average pack current. The I²C interface lets the host set the charge current, voltage thresholds, and input current limit, so the same BOM can serve different pack capacities by firmware alone.
28-VQFN exposed pad — thermal and rework note
The 28-VQFN (5x5 mm) package with exposed pad is the standard QFN footprint for a charger this size. The thermal pad under the part is the primary heat path — the board needs a matching copper land and at least four vias to the inner ground plane to keep the junction below 125°C at 8 A charge.