FAN5358_10 Datasheet, PDF (1/13 Pages) Fairchild Semiconductor – 2MHz, 500mA, SC70 Synchronous Buck Regulator

September 2010
FAN5358
2MHz, 500mA, SC70 Synchronous Buck Regulator
Features
ƒ 2MHz Nominal-Frequency Operation
ƒ 25µA Typical Quiescent Current
ƒ 500mA Output Current Capability
ƒ 2.7V to 5.5V Input Voltage Range
ƒ 1.0 to 1.8V Fixed Output Voltages
ƒ Low Ripple, Light-Load PFM Mode
ƒ Internal Soft-Start
ƒ Input Under-Voltage Lockout (UVLO)
ƒ Thermal Shutdown and Overload Protection
ƒ 6-lead 2 x 2.2mm SC70
Applications
ƒ Cell Phones, Smart Phones
ƒ 3G, 4G, WiFi^®, WiMAX™, and WiBro^® Data Cards
ƒ Netbooks^®, Ultra-Mobile PCs
Description
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
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 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.
Typical Application
L1 _{SW 1}
6 ^VIN
GND ₂
U1
5 ^GND
C_IN
VOUT ₃
C_OUT
4 ^EN
Figure 1. FAN5358 Typical Application
Table 1. External Components for Figure 1
U1
FAN5358
f_SW
2MHz
L1
2.2μH
C_IN
2.2μF
C_OUT
4.7μF
Trademarks are the property of their respective owners.
© 2009 Fairchild Semiconductor Corporation
FAN5358 • Rev. 1.0.2
www.fairchildsemi.com