Buck-boost charger with I²C programmability for 1-5 cell packs
The Texas Instruments BQ25731RSNR is an I²C-controlled, NVDC (narrow-voltage DC) buck-boost battery charger designed for multi-chemistry battery packs of 1 to 5 series cells. The charger integrates over-current, over-temperature, and over-voltage fault protection, and is packaged in a 32-pin WFQFN with exposed pad for thermal management.
16.2A charge current — sizing the power stage
The 16.2A maximum charge current is the headline rating for this part. That level of current targets battery packs in the 2-5 cell range where fast charging is required. The constant-current programming is set via I²C, so the charge profile can be adjusted in firmware without a resistor change.