The LTC®3225 is a programmable supercapacitor charger designed to charge two supercapacitors in series to a fi xed output voltage (4.8V/5.3V selectable) from a 2.8V/3V to 5.5V input supply. Automatic cell balancing prevents overvoltage damage to either supercapacitor. No balancing resistors are required. Low input noise, low quiescent current and low external parts count (one fl ying capacitor, one bypass capacitor at VIN and one programming resistor) make the LTC3225 ideally suited for small battery-powered applications. Charging current level is programmed with an external resistor. When the input supply is removed, the LTC3225 automatically enters a low current state, drawing less than 1μA from the supercapacitors. The LTC3225 is available in a 10-lead 3mm × 2mm DFN package.