General Description

The MAX770–MAX773 step-up switching controllers provide 90% efficiency over a 10mA to 1A load. A unique current-limited pulse-frequency-modulation (PFM) control scheme gives these devices the benefits of pulse-width-modulation (PWM) converters (high efficiency at heavy loads), while using less than 110µA of supply current (vs. 2mA to 10mA for PWM converters).

Features

♦ 90% Efficiency for 10mA to 1A Load Currents

♦ Up to 15W Output Power

♦ 110µA Max Supply Current

♦ 5µA Max Shutdown Current

♦ 2V to 16.5V Input Range (MAX770/MAX771/MAX772)

♦ Internal Shunt Regulator for High Input Voltages (MAX773)

♦ Preset or Adjustable Output Voltages

   MAX770: 5V or Adjustable

   MAX771: 12V or Adjustable

   MAX772: 15V or Adjustable

   MAX773: 5V, 12V, 15V, or Adjustable

♦ Current-Limited PFM Control Scheme

♦ 300kHz Switching Frequency

Applications

    Palmtops/Handy-Terminals

    High-Efficiency DC-DC Converters

    Battery-Powered Applications

    Positive LCD-Bias Generators

    Portable Communicators

    Flash Memory Programmers