Single-cell Li-Po charger with 125°C junction capability
The Texas Instruments BQ24013DRCRG4 is a linear charger IC from the bqTINY™ family, designed for single-cell Lithium Ion or Lithium Polymer battery packs. It terminates at 4.2V and delivers a programmable charge current up to 1A, with the actual current set by an external resistor. That headroom matters when the charger sits near a motor driver, a power stage, or inside a sealed enclosure where ambient heat builds — the linear regulator doesn't throttle back until the die actually hits the limit.
The charge current is constant-current programmable via a single resistor (ISET pin), not a fixed internal value. That means the same BQ24013DRCRG4 can charge a 500 mAh cell at 500 mA or a 2000 mAh pouch at 1 A — the BOM resistor value sets the rate. The 1A max is the ceiling; stay at or below it for the cell's C-rate. Short-circuit protection is built in — if the output is shorted, the device enters a fault state and limits current. No external crowbar or P-channel disconnect FET needed for basic protection, though the board still needs proper input fusing for the supply line. The 16.5V absolute maximum on the input supply gives margin for a 5V USB rail or a 12V wall adapter without an external pre-regulator.
Package and footprint — what the layout engineer needs
The datasheet's recommended land pattern calls for a 2.1x2.1 mm solder-defined pad on the top layer with at least four vias connecting to the ground plane. Without that thermal path, the 1A charge current at elevated input voltage will trigger the thermal regulation loop and reduce the charge rate.
Sourcing posture — active part, no supply risk
No second-source or direct replacement is listed in the Texas Instruments portfolio; the BQ24013 family shares the same die and pinout across the DRCR and DRCRG4 suffix variants, with the G4 indicating RoHS-compliant green packaging.