The MAX1565 provides a complete power-supply solution for digital still and video cameras through the integration of ultra-high-efficiency step-up/step-down DC-to-DC converters along with three auxiliary step-up controllers. The MAX1565 is targeted for applications that use either 2 or 3 alkaline or NiMH batteries as well as those using a single lithium-ion (Li+) battery. The step-up DC-to-DC converter accepts inputs from 0.7V to 5.5V and regulates a resistor-adjustable output from 2.7V to 5.5V. It uses internal MOSFETs to achieve 95% efficiency. Adjustable operating frequency facilitates design for optimum size, cost, and efficiency. The step-down DC-to-DC converter can produce output voltages as low as 1.25V and also utilizes internal MOSFETs to achieve 95% efficiency. An internal softstart ramp minimizes surge current from the battery. The converter can operate from the step-up output providing buck-boost capability with up to 90% compound efficiency, or it can run directly from the battery if buckboost operation is not needed. The MAX1565 features auxiliary step-up controllers that power CCD, LCD, motor actuator, and backlight circuits. The device also features low-cost expandability by supplying power, an oscillator signal, and a reference to the MAX1801 SOT23 slave controller that supports step-up, SEPIC, and flyback configurations.