2MHz, 500mA, SC70 Synchronous Buck Regulator
2MHz Nominal-Frequency Operation
25µA Typical Quiescent Current
500mA Output Current Capability
2.7V to 5.5V Input Voltage Range
1.0 to 1.8V Fixed Output Voltages
Low Ripple, Light-Load PFM Mode
Input Under-Voltage Lockout (UVLO)
Thermal Shutdown and Overload Protection
6-lead 2 x 2.2mm SC70
Cell Phones, Smart Phones
3G, 4G, WiFi®, WiMAX™, and WiBro® Data Cards
Netbooks®, Ultra-Mobile PCs
The FAN5358 is a step-down switching voltage regulator that
delivers a fixed output from an input voltage supply of 2.7V to
5.5V. Using a proprietary architecture with synchronous
rectification, the device is capable of delivering 500mA and
maintaining a very high efficiency of over 80% at load currents
as low as 1mA. The regulator operates at a nominal frequency
of 2MHz, which reduces the value of the external components
to as low as 2.2μH for the output inductor and 4.7µF for the
At moderate and light loads, pulse frequency modulation is
used to operate the device in power-save mode with a typical
quiescent current of 25µA. Even with such a low quiescent
current, the part exhibits excellent transient response during
large load swings. In shutdown mode, the supply current
drops below 1µA, reducing power consumption.
FAN5358 is available in a 6-lead SC70 package.
L1 SW 1
GND 2 U1 5 GND CIN
Figure 1. FAN5358 Typical Application
Table 1. External Components for Figure 1
Wi-Fi® is a registered trademark of Wi-Fi Alliance Corporation.
WiMax™ is a trademark of WIMAX Forum Corporation.
WiBro® is a registered trademark of Telecommunications Technology Association.
Netbooks® is a registered trademark of Netbooks, Inc.
© 2009 Fairchild Semiconductor Corporation
FAN5358 • Rev. 1.0.1