AAT3686

The AAT3686 BatteryManager is a highly integrated single- cell lithium-ion/polymer battery charger IC designed to operate with USB port and AC adapter inputs. It requires the minimum number of external components.

The AAT3686 precisely regulates battery charge voltage and current for 4.2V lithium-ion/polymer battery cells. Adapter charge current rates can be programmed up to 1.5A. In the absence of an adapter and with a USB port connected, the battery can also be charged by USB power.

Depending on the USB port type, the AAT3686 charge current can be programmed for two separate levels up to 500mA. An optional Charge Reduction Loop is also built in to allow users to charge the battery with available current from a USB port, while keeping the port voltage regulated. USB charging is disabled when an adapter is present.

Battery temperature and charge state are fully monitored for fault conditions. In the event of an over-voltage or over-temperature failure, the AAT3686 device will automatically shut down, thus protecting the charging device, control system, and the battery under charge. Status monitor output pins are provided to indicate the battery charge status by directly driving two external LEDs. A serial interface output is available to report 22 various status states to a microcontroller.

The AAT3686 is available in a Pb-free, thermallyenhanced, space-saving TDFN34-16 (3x4mm) or TDFN44-16 (4x4mm) package and is rated over the -40°C to +85°C temperature range.