MAX1565

19-2712; Rev 0; 1/03 KIT ATION EVALU E L B A AVAIL Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply General Description Features o Step-Up DC-to-DC Converter 95% Efficient 3.3V (Fixed) or 2.7V to 5.5V (Adjustable) Output Voltage o Step-Down DC-to-DC Converter Operate from Battery for 95% Efficient Buck Combine with Step-Up for 90% Efficient BuckBoost Adjustable Output Down to 1.25V o Three Auxiliary PWM Controllers o Up to 1MHz Operating Frequency o 1µA Shutdown Mode o Internal Soft-Start Control o Overload Protection o Compact 32-Pin, 5mm x 5mm Thin QFN Package MAX1565 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 out...