Active production — fit for a 3- or 4-cell battery BOM
The Texas Instruments BQ24721CRHBR is an active-production multi-chemistry battery charger IC supporting 3 to 4 series cells with a maximum pack voltage of 19.2 V. The I2C interface lets the host controller set the charge current and monitor status, while the integrated overcurrent protection guards the pack and the charging path.
Supply rail and package — 24 V max input in a 5x5 mm QFN
Surface-mount assembly with standard reflow profiles works; the exposed pad demands a solder-paste stencil aperture that covers at least 50% of the pad area for reliable void-free solder joint.
Temperature grade and chemistry flexibility
The multi-chemistry support means it can charge Li-ion, Li-polymer, or LiFePO4 stacks — the host firmware selects the termination voltage and charge algorithm via the I2C bus. Programmable current allows the same charger design to serve different battery capacities without a resistor change.