Single-cell Li-Ion charger with I²C programmability
The Texas Instruments BQ24262YFFT is a single-cell Lithium Ion battery charger IC that uses an I²C interface to set the charge current and battery regulation voltage. It delivers a programmable constant charge current up to 3 A maximum, targeting the 4.2 V battery pack voltage typical of Li-Ion cells.
The 3 A maximum charge current sets the power-stage inductor and input capacitor sizing. At 3 A continuous, the input supply must deliver at least 6 V (the supply maximum) with headroom for the linear dropout. The I²C interface allows the host MCU to adjust the charge current dynamically — useful for thermal throttling or USB input current limiting — but requires an I²C bus pull-up and a dedicated GPIO for the charge-enable line. Because the charge current is constant-programmable rather than resistor-set, the BOM saves one precision resistor but adds a firmware dependency. The 36-DSBGA package (2.63 x 2.46 mm) demands a controlled solder-paste stencil and X-ray inspection for voiding under the bumps — not a hand-solder part.
The BQ24262YFFT carries an Obsolete lifecycle status. Buyers should verify the lot date code and moisture-sensitivity level (MSL) before reflow, as DSBGA packages absorb moisture quickly and may require a pre-bake if the shelf life has been exceeded.