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 800µA Supply Current

♦ 0.6µA Shutdown Current

♦ Drives External P-Channel FETs

♦ Cycle-by-Cycle Current Limiting

♦ 2V ±1.5% 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