RT8008
1.5MHz, 600mA, High Efficiency PWM Step-Down DC/DC
Converter
General Description
The RT8008 is a high-efficiency pulse-width-modulated
(PWM) step-down DC-DC converter. Capable of delivering
600mA output current over a wide input voltage range from
2.5V to 5.5V, the RT8008 is ideally suited for portable
electronic devices that are powered from 1-cell Li-ion
battery or from other power sources within the range such
as cellular phones, PDAs and handy-terminals.
Internal synchronous rectifier with low R
DS(ON)
dramatically
reduces conduction loss at PWM mode. No external
Schottky diode is required in practical application. The
RT8008 automatically turns off the synchronous rectifier
while the inductor current is low and enters discontinuous
PWM mode. This can increase efficiency at light load
condition.
The RT8008 enters Low-Dropout mode when normal PWM
cannot provide regulated output voltage by continuously
turning on the upper P-MOSFET. RT8008 enter shutdown
mode and consumes less than 0.1µA when EN pin is pulled
low.
The switching ripple is easily smoothed-out by small
package filtering elements due to a fixed operation
frequency of 1.5MHz. This along with small SOT-23-5 and
TSOT-23-5 package provides small PCB area application.
Other features include soft start, lower internal reference
voltage with 2% accuracy, over temperature protection,
and over current protection.
Features
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+2.5V to +5.5V Input Range
Adjustable Output From 0.6V to V
IN
1.0V, 1.2V, 1.5V, 1.8V, 2.5V and 3.3V Fixed/
Adjustable Output Voltage
600mA Output Current, 1A Peak Current
95% Efficiency
No Schottky Diode Required
1.5MHz Fixed-Frequency PWM Operation
Small SOT-23-5 and TSOT-23-5 Package
RoHS Compliant and 100% Lead (Pb)-Free
Applications
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Cellular Telephones
Personal Information Appliances
Wireless and DSL Modems
MP3 Players
Portable Instruments
Ordering Information
RT8008(-
)
Package Type
B : SOT-23-5
J5 : TSOT-23-5
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Output Voltage
Default : Adjustable
10 : 1.0V
12 : 1.2V
15 : 1.5V
18 : 1.8V
25 : 2.5V
33 : 3.3V
Note :
RichTek Pb-free and Green products are :
Pin Configurations
(TOP VIEW)
EN
GND
LX
1
2
3
4
VIN
5
FB/VOUT
}
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
SOT-23-5/TSOT-23-5
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Suitable for use in SnPb or Pb-free soldering processes.
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100% matte tin (Sn) plating.
DS8008-04 March 2007
www.richtek.com
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RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
