Analog Devices MAX1734 Product Info

• 250mA Guaranteed Output Current
• Synchronous Rectifier for Over 90% Efficiency
• Tiny 5-Pin SOT23 Package
• 40µA Quiescent Supply Current
• 0.01µA Logic-Controlled Shutdown
• Up to 1.2MHz Switching Frequency
• Fixed 1.8V or 1.5V Outputs (MAX1734)
• Adjustable Output Voltage (MAX1733)
• ±1.5% Initial Accuracy
• 2.7V to 5.5V Input Range
• Soft-Start Limits Startup Current

The MAX1733/MAX1734 step-down DC-DC converters deliver over 250mA to outputs as low as 1.25V. These converters use a unique proprietary current-limited control scheme that achieves over 90% efficiency. These devices maintain extremely low quiescent supply current (40µA), and their high 1.2MHz (max) operating frequency permits small, low-cost external components. This combination of features makes the MAX1733/ MAX1734 excellent high-efficiency alternatives to linear regulators in space-constrained applications.

Internal synchronous rectification greatly improves efficiency and eliminates the external Schottky diode required in conventional step-down converters. Both devices also include internal digital soft-start to limit input current upon startup and reduce input capacitor requirements.

The MAX1733 provides an adjustable output voltage (1.25V to 2.0V). The MAX1734 provides factory-preset output voltages (see Selector Guide). Both are available in space-saving 5-pin SOT23 packages.

Applications

• Cell Phones
• Computers: Desktop, Workstation, Server
• Consumer Audio
• Digital Still Cameras
• Global Positioning Systems (GPS)
• Palmtop Computers
• POS Terminals
• Wireless Data
• Wireless Local Area Networks (WLANs)