Single-cell Li-ion charger with I²C programmability
The Texas Instruments BQ24153YFFR is a single-cell linear charger for Lithium Ion or Lithium Polymer battery packs, with a maximum charge current of 1.25 A and a maximum battery regulation voltage of 4.44 V. Charge parameters — current and safety timer — are set through the I²C interface rather than external resistors, which saves board area and allows dynamic adjustment by the system host. The device integrates over-voltage and over-temperature fault protection, a requirement for safe single-cell charging in portable equipment.
Charge current ceiling and thermal budget
At the 1.25 A maximum charge current, the linear regulator dissipates the voltage drop between the 6 V max supply and the battery voltage as heat. In a 20-DSBGA package with no exposed thermal pad, the PCB copper area under the device sets the effective thermal resistance — layout is not optional.
20-DSBGA package — what it means for assembly and rework
The 20-DSBGA (0.4 mm pitch wafer-level package) requires a solder stencil designed for the small aperture size and a reflow profile that matches the JEDEC MSL level. The package is moisture-sensitive; a bake before rework is standard practice if the floor life has been exceeded.
