Host-Controlled Multi-Chemistry Battery Charger with Low Input Power Detect and low Iq

The bq24704 is a high-efficiency, synchronous battery charger with integrated compensation offering low component count for space-limited Li-Ion and Li-Polymer battery charging applications. Charge current and voltage programming allows high regulation accuracies, and can be either hardwired with resistors, or programmed by the system power-management microcontroller using a DAC or GPIOs.

The bq24704 charges two, three, or four series Li+ cells, supporting up to 8 A of charge current, and is available in a 24-pin, 4x4-mm thin QFN package.

The bq24704 features Dynamic Power Management (DPM) and input power limiting. These features reduce battery charge current when the input power limit is reached to avoid overloading the AC adapter when supplying the load and the battery charger simultaneously. A highly-accurate current-sense amplifier enables precise measurement of input current from the AC adapter to monitor the overall system power.