The MAX1947 is a compact, high-efficiency, step-up DCDC converter that regulates output voltages from 1.8V to 3.3V to power P/DSP cores, memory, and I/O rails in 1and 2-cell alkaline/NiMH/NiCd battery-powered systems. It features an internal 800mA switch and synchronous rectifier to achieve up to 94% efficiency and to eliminate the need for an external Schottky diode. High-frequency switching (up to 2MHz) results in low ripple and small external components, while automatic pulse skipping at light loads reduces supply current to just 70A for extended battery life. Maxim's proprietary True ShutdownTM reduces supply current to just 2A and fully discharges the output to ground. The converter is offered in fixed-output voltages of 1.8V, 2.5V, 3.0V, and 3.3V, requiring no feedback or compensation network. A 75ms RESET output flag provides for power-on reset (POR) and undervoltage detection. The MAX1947 is available in a space-saving 8-pin TDFN package.