Single-cell Li-ion linear charger — 30 mA ceiling
The BQ24901PW is a Texas Instruments linear charge-management IC for single-cell Lithium Ion or Lithium Polymer packs, with a maximum charge current of 30 mA and a regulated battery voltage of 4.2 V. It integrates short-circuit fault protection and offers programmable charge current and charge-timer features, making it suitable for low-capacity coin-cell or small-format Li-ion applications where the charge rate stays under 30 mA.
The 30 mA charge-current ceiling sets the practical battery capacity this part can handle — a 100 mAh cell charges at roughly C/3, a 200 mAh cell at C/6.7, so the charge time scales inversely with the current limit. Operating temperature spans -20°C to 85°C, which covers most portable and industrial indoor environments but not extended automotive or high-temp enclosure duty.