The LTC3225/LTC3225-1 are programmable supercapacitor chargers designed to charge two supercapacitors in series to a selectable fixed output voltage (4.8V/5.3V for the LTC3225 and 4V/4.5V for the LTC3225-1) from input supplies as low as 2.8V to 5.5V. 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 flying capacitor, one bypass capacitor at VINand one programming resistor) make the LTC3225/LTC3225-1 ideally suited for small battery-powered applications.Charge current level is programmed with an external resistor. When the input supply is removed, the LTC3225/LTC3225-1 automatically enter a low current state, drawing less than 1μA from the supercapacitors.The LTC3225/LTC3225-1 are available in a 10-lead 2mm × 3mm DFN package.ApplicationsCurrent Limited Applications with High Peak Power Loads (LED Flash, PCMCIA Tx Bursts, HDD Bursts, GPRS/GSM Transmitter)Backup Supplies