Charge current and thermal budget
The BQ24003PWPR is a single-cell Li-Ion linear charger from Texas Instruments, delivering a constant-current charge up to 1.2A max into a 4.2V battery pack. The 20-HTSSOP package has an exposed thermal pad — the 1.2A ceiling assumes adequate PCB copper area to pull heat off the die; in a tight layout the charge current may need to be set lower to stay below the over-temperature shutdown threshold.
Programmable current and timer — no I2C needed
Charge current and safety timer are set with external resistors, so the BQ24003PWPR fits into designs where a simple analog control loop is preferred over a digital bus. The timer provides a backup termination if the battery never reaches the 4.2V regulation voltage within the programmed window.
Protection and temperature range
On-chip over-temperature protection shuts down the charger if the die temperature exceeds the safe limit — a useful safeguard when charging at the full 1.2A in a warm enclosure. The device is specified over -40°C to 70°C ambient, covering consumer and industrial indoor equipment where the charger sits near the battery pack.