General Description

The MAX8655 synchronous-PWM buck regulator operates from a 4.5V to 25V input and generates an output voltage adjustable from 0.7V to 5.5V at loads up to 25A. Integrated power MOSFETs provide a small footprint, ease of layout, and reduced EMI. Removing the board trace inductances ensures the highest efficiency at high frequency.

The MAX8655 uses peak current-mode control architecture with an adjustable (200kHz to 1MHz), constant

switching frequency, which is externally synchronizable.

The MAX8655’s adjustable current limit uses the inductor’s DC resistance to improve efficiency or an external sense resistor for higher accuracy. Foldback type current limit is available to reduce the power dissipation under severe-overload or short-circuit conditions. A reference input is provided for use with a high-accuracy external reference or for DDR and tracking applications.

Features

♦ 25A Output Current

♦ Integrated Power MOSFETs

♦ Operates from 4.5V to 25V Supply

♦ 1 FB Voltage Accuracy Over Temperature

♦ Adjustable Output Voltage Down to 0.7V

♦ Adjustable Switching Frequency and External

   Synchronization from 200kHz to 1MHz

♦ 180° Phase-Shifted Synchronization

♦ Adjustable Overcurrent Limit

♦ Adjustable Slope Compensation

♦ Selectable Current-Limit Mode: Latch-Off or Automatic Recovery

♦ Monotonic Output Voltage Rise at Startup into Prebias Output

♦ Output Sources and Sinks Current for DDR Applications

♦ Enable Input

♦ Power-OK (POK) Output

♦ Adjustable Soft-Start

♦ Independently Adjustable Overvoltage Protection

Applications

   Point-of-Load Power Supplies

   Telecom Power

   Networking

   Nonisolated DC-DC Power Modules

   Servers and Workstations

   Notebook Computers

   IBA Power Supplies