5 A charge current, 1–4 cells — the BOM-fit decision
The BQ25790YBGR is a TI I²C-controlled buck-boost charger for 1–4 series Li-ion or Li-polymer cells. The 5 A max charge current and 18.8 V max battery pack voltage define the charge-time floor and the cell-count ceiling for a portable or battery-backup design. The 24 V supply maximum gives headroom for USB-C PD or a 19 V adapter without a separate pre-regulator.
Fault protection set — what it covers
The charger integrates over-current, over-temperature, over-voltage, reverse battery, and short-circuit protection. That coverage means the external supervisory circuit can be pared back — the part itself handles the common failure modes a Li-ion pack can present during charging or a reverse-plug event.
Package and layout — 56-DSBGA 2.9x3.32 mm
The 56-DSBGA (2.9x3.32 mm) package is a 0.4 mm pitch BGA. The small footprint suits space-constrained portable products, but the fine pitch demands a controlled-impedance PCB stack-up and a via-in-pad process for the centre thermal pad.