The FAN5350 is a step-down switching voltage regulator that delivers a fixed 1.82V from an input voltage supply of 2.7V to 5.5V. Using a proprietary architecture with synchronous rectification, the FAN5350 is capable of delivering 600mA at over 90% efficiency, while maintaining a very high efficiency of over 80% at load currents as low as 1mA. The regulator operates at a nominal fixed frequency of 3MHz at full load, which reduces the value of the external components to 1µH for the output inductor and 4.7µF for the output capacitor.

At moderate and light loads, pulse frequency modulation is used to operate the device in power-save mode with a typical quiescent current of 16µA. Even with such a low quiescent current, the part exhibits excellent transient response during large load swings. At higher loads, the system automatically switches to fixed-frequency control, operating at 3MHz. In shutdown mode, the supply current drops below 1µA, reducing power consumption.

The FAN5350 is available in a 6-lead Molded Leadless Package (MLP) and a 5-bump Wafer Level Chip Scale Package (WLCSP).

• 3MHz Fixed-Frequency Operation
• 16µA Typical Quiescent Current
• 600mA Output Current Capability
• 2.7V to 5.5V Input Voltage Range
• 1.82V Fixed Output Voltage
• Synchronous Operation
• Power-Save Mode
• Soft-Start Capability
• Input Under-Voltage Lockout (UVLO)
• Thermal Shutdown and Overload Protection
• 6-Lead 3 x 3mm MLP
• 5-Bump 1 x 1.37mm WLCSP

• Cell Phones, Smart-Phones
• Pocket PCs
• WLAN DC-DC Converter Modules
• PDA, DSC, PMP, and MP3 Players
• Portable Hard Disk Drives