The FAN4855 is a low power boost regulator designed for low voltage DC to DC conversion in 2-cell battery powered systems such as digital cameras, cell phones and PDAs. The converter starts-up at 1.3V and operates after the start at an input voltage as low as 1V. Output voltage can be adjusted by external resistors from 3.3V to 5V with a maximum load current of 0.5A. Quiescent current in shut-down mode is less than 10A, which maximizes the battery live time. The ON time changes with the input voltage to maintain the ripple current constant and to provide the highest efficiency over a wide load range--while maintaining low peak currents in the boost inductor. The combination of built-in power transistors, synchronous rectification and low supply current, make the FAN4855 ideal for portable applications. The FAN4855 is available in 8-lead MSOP and TSSOP packages.