LT1512

The LT^®1512 is a 500kHz current mode switching regula-tor specially configured to create a constant-current/constant-voltage battery charger. In addition to the usualvoltage feedback node, it has a current sense feedbackcircuit for accurately controlling output current of a flybackor SEPIC (Single-Ended Primary Inductance Converter)topology charger. These topologies allow the currentsense circuit to be ground referred and completely sepa-rated from the battery itself, simplifying battery switchingand system grounding problems. In addition, these to-pologies allow charging even when the input voltage islower than the battery voltage.

Maximum switch current on the LT1512 is 1.5A. Thisallows battery charging currents up to 1A for a singlelithium-ion cell. Accuracy of 1% in constant-voltage modeis perfect for lithium battery applications. Charging cur-rent can be easily programmed for all battery types.