SEPIC Constant-Current and Constant Voltage Battery Charger IC
The LT®1512 is a 500kHz current mode switching regulator specially configured to create a constant-current/constant-voltage battery charger. In addition to the usual voltage feedback node, it has a current sense feedback circuit for accurately controlling output current of a flyback or SEPIC (Single-Ended Primary Inductance Converter) topology charger. These topologies allow the current sense circuit
to be ground referred and completely separated from the battery itself, simplifying battery switching and system grounding problems.
Maximum switch current on the LT1512 is 1.5A. This allows battery charging currents up to 1A for a single lithium-ion cell.
Features
Charger Input Voltage May Be Higher, Equal to or Lower Than Battery Voltage
Charges Any Number of Cells Up to 30V*
1% Voltage Accuracy for Rechargeable Lithium Batteries
500kHz Switching Frequency Minimizes Inductor Size
100mV Current Sense Voltage for High Efficiency
Battery Can Be Directly Grounded
Charging Current Easily Programmable or Shut Down
Applications
Battery Charging of NiCd, NiMH, Lead-Acid or Lithium Rechargeable Cells
