General Description

The MAX8680 highly efficient complete power-supply solution is designed for digital still cameras (DSCs) and digital video cameras (DVCs). The device integrates seven on-chip power MOSFET DC-DC converters with up to 95 efficiency to power all critical power supplies in DSC systems. Each converter also features True Shutdown?, as well as internal compensation to minimize external component count. The seven DC-DC converter outputs are:

? Step-up synchronous-rectified DC-DC converter (SU). The MAX8680 is bootstrapped from VSU.

? MAIN synchronous-rectified step-down DC-DC converter (M) for DSP I/O supply voltage.

? DDRZ synchronous-rectified step-down DC-DC converter (Z) for DSP DDR supply voltage.

? Low-voltage (down to 1V) synchronous-rectified step-down DC-DC converter (SD) for DSP core supply voltage.

? High-voltage, step-up DC-DC converter with current regulation and PWM dimming control (LEDBST) for white LEDs (WLED).

? High-voltage step-up DC-DC converter (CCDBST) for CCD imagers or positive LCD bias supplies.

? Transformerless inverting DC-DC converter (CCDINV) for CCD imagers or negative LCD bias supplies.

Features

? 95 Efficient Synchronous-Rectified DC-DC Converters

? 90 Efficient Boost-Buck Operation

? 85 Efficient DC-DC Converters for CCD, LCD, WLED, and/or OLED

? Internal Compensation on All Channels

? True Shutdown on All Step-Up Converters

? Overload Protection

? Soft-Start for Controlled Startup Current

? Dropout Operation (100 Duty Cycle) on StepDown Converters

? Regulated Current Output for Up to 6 White LEDs

? PWM Dimming of WLED Current

? Adjustable LED Overvoltage Protection Up to 27V

? Transformerless Inverting Converter for CCD

? 2MHz Switching Frequency for Low-Voltage Channels

? ±2.5 Switching Frequency Accuracy

? 1μA Shutdown Supply Current

? Power-On Voltage Tracking for Core and Main Outputs

? All Internal Power MOSFETs

? SDOK Power-OK Indicator

Applications

?? DSCs and DVCs

?? PDAs and Portable Media Players

?? GPS Navigation Systems