FAN2001: High-efficiency step-down DC/DC converter

Designed for use in battery-powered applications, the FAN2001/FAN2002 is a high-efficiency, low-noise synchronous PWM current mode and Pulse Skip (Power Save) mode DC-DC converter. It can provide up to 1A of output current over a wide input range from 2.5V to 5.5V. The output voltage can be externally adjusted over a wide range of 0.8V to 5.5V by means of an external voltage divider.      At moderate and light loads, pulse skipping modulation is used. Dynamic voltage positioning is applied, and the output voltage is shifted 0.8% above nominal value for increased headroom during load transients. At higher loads the system automatically switches over to current mode PWM control, operating at 1.3 MHz. A current mode control loop with fast transient response ensures excellent line and load regulation. To achieve high efficiency and ensure long battery life, the quiescent current is reduced to 25µA in Power Save mode, and the supply current drops below 1µA in shut-down mode. The FAN2001/FAN2002 is available in 3x3mm 6-lead MLP package.

Features

• 96% Efficiency, Synchronous Operation
• Adjustable Output Voltage Options from 0.8V to V_IN
• 2.5V to 5.5V Input Voltage Range
• Up to 1A Output Current
• Fixed Frequency 1.3MHz PWM Operation
• High Efficiency Power Save Mode
• 100% Duty Cycle Low Dropout Operation
• Soft Start
• Output Over-Voltage Protection
• Dynamic Output Voltage Positioning
• 25µA Quiescent Current
• Thermal Shutdown and Short Circuit Protection
• Pb-Free 3x3mm 6-Lead MLP PackageApplications
• Pocket PCs, PDAs
• Cell Phones
• Battery-Powered Portable Devices
• Digital Cameras
• Hard Disk Drives
• Set-Top-Boxes
• Point-of-Load Power
• Notebook Computers
• Communications Equipment

Application Notes