Battery Charger Employs Unique Loops

Designed to operate off USB and ac-adapter inputs, the AAT3686 li-ion/polymer battery charger features digital thermal and charge-reduction loops that allow charging the battery from the USB port while keeping the port voltage regulated. The latter feature ensures the charge function will not overload the USB port if other system loads use the same source. The device supports programmable charge rates up to 1.5A. USB charge rates are programmable for high and low levels. Other features include temperature and charge state monitoring, over-voltage and over-temperature protection, automatic shut down circuits, and the ability to report up to 22 unique charging-status states to a microcontroller via a serial interface output. Available in a lead-free, 16-pin 4 mm x 4 mm TDFN package, price is $1.64 each/1,000. ANALOGIC TECHNOLOGIES INC., Sunnyvale, CA. (408) 737-4600