Single-cell Li-Ion charger with I²C control
The Texas Instruments BQ21061YFPT is a single-cell linear battery charger IC for Lithium Ion/Polymer packs. It delivers a programmable charge current up to 500 mA, set via the I²C interface or an external resistor. Overcurrent protection is built in. The part operates from a 5.25 V max supply and is rated over -40°C to 85°C, suiting portable and wearable devices where board space is tight.
500 mA charge current — sizing the charge time
The 500 mA maximum charge current sets the charge rate for a single-cell Li-Ion pack. The current is constant and programmable.
I²C interface — what it buys you
The I²C bus lets the system host adjust the charge current on the fly, read fault flags, and control the charge cycle without extra GPIOs. That is useful in multi-chemistry or multi-capacity product lines — one BOM, firmware-selectable current. The interface is the only programmable feature listed; no voltage or termination-current registers are confirmed in this record, so treat the current as the primary I²C-controlled parameter.
20-DSBGA — footprint and assembly
The 20-DSBGA package is surface-mount. The supplier device package is 20-DSBGA.