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General Description

The MAX747 high-efficiency, high-current, step-down controller drives external P-channel FETs. It provides 90 to 95 efficiency from a 6V supply with load currents ranging from 50mA up to 2.5A. It uses a pulse-width-modulating (PWM) current-mode control scheme to provide precise output regulation and low output noise. The MAX747¡¯s 4V to 15V input voltage range, a fixed 5V/adjustable (Dual-Mode?) output, and a current limit set with an external resistor make this device ideal for a wide range of applications.

Features

? 90 to 95 Efficiency for 50mA to 2.5A

?? Output Currents

? 4V to 15V Input Voltage Range

? Low 800?A Supply Current

? 0.6?A Shutdown Current

? Drives External P-Channel FETs

? Cycle-by-Cycle Current Limiting

? 2V ¡À1.5 Accurate Reference Output

? Adjustable Soft-Start

? Precision Comparator for Power-Fail or

?? Low-Battery Warning

Applications

?? Notebook Power Supplies

?? Personal Digital Assistants

?? Battery-Operated Equipment

?? Cellular Phones

?? 5V to 3.3V Green PC Applications