RT8057 Datasheet, PDF (1/11 Pages) Richtek Technology Corporation – 2.25MHz 1A Synchronous Step-Down Converter

RT8057
2.25MHz 1A Synchronous Step-Down Converter
General Description
The RT8057 is a high efficiency Pulse-Width-Modulated
(PWM) step-down DC/DC converter, capable of delivering
1A output current over a wide input voltage range from 2.7V
to 5.5V. The RT8057 is ideally suited for portable electronic
devices that are powered from 1-cell Li-ion battery or from
other power sources such as cellular phones, PDAs, hand-
held devices, game console and related accessories.
The internal synchronous rectifier with low R_DS(ON)
dramatically reduces conduction loss at PWM mode.
No external Schottky diode is required in practical
applications. The RT8057 enters Low Dropout Mode when
normal Pulse -Width Mode cannot provide regulated output
voltage by continuously turning on the upper P-MOSFET.
The RT8057 enters shut-down mode and consumes less
than 1μA when the EN pin is pulled low. The switching
ripple is easily smoothed-out by small package filtering
elements due to a fixed operating frequency of 2.25MHz.
The RT8057 is available in a small WDFN-6SL 2x2 package.
Ordering Information
RT8057
(2)
Taping Type ( Pin1 at Q2)
Package Type
QW : WDFN-6SL 2x2 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Features
z 2.7V to 5.5V Wide Input Operation Range
z 2.25MHz Fixed-Frequency PWM Operation
z Up to 1A Output Current
z Up to 90% Efficiency
z 0.6V Reference Allows Low Output Voltage
z Internal Soft-Start
z No Schottky Diode Required
z Internal Compensation to Reduce External
Components
z Low Dropout Operation : 100% Duty Cycle
z RoHS Compliant and Halogen Free
Applications
z Portable Instruments
z Game Console and Accessories
z Microprocessors and DSP Core Supplies
z Cellular Phones
z Wireless and DSL Modems
z PC Cards
Pin Configurations
(TOP VIEW)
LX 1
NC 2
FB 3
6 GND
5 VIN
7 4 EN
WDFN-6SL 2x2
Marking Information
J7 : Product Code
J7W
W : Date Code
DS8057-03 November 2011
www.richtek.com
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