The LTC3355 is a complete input power interrupt ride-through DC/DC system. The part charges a supercapacitor while delivering load current to VOUT, and uses energy from the supercapacitor to provide continuous VOUTbackup power when VINpower is lost. The LTC3355 contains a nonsynchronous constant frequency current mode monolithic 1A buck switching regulator to provide a 2.7V to 5V regulated output voltage from an input supply of up to 20V.A 1A programmable CC/CV linear charger charges the supercapacitor from VOUT. When the VINsupply drops below the PFI threshold, the devices’s constant frequency nonsynchronous current mode 5A boost switching regulator delivers power from the supercapacitor to VOUT. A thermal regulation loop maximizes charge current while limiting the die temperature to 110°C. The IC has boost, charger and VINprogrammable current limits. The LTC3355 is available in a 20-lead 4mm × 4mm QFN surface mount package.ApplicationsRide-Through "Dying Gasp" SuppliesPower Meters/Industrial Alarms/Solid State Drives