RT8059 Datasheet, PDF (1/10 Pages) Richtek Technology Corporation – 1.5MHz, 1A, High Efficiency PWM Step-Down DC/DC Converter

®
RT8059
1.5MHz, 1A, High Efficiency PWM Step-Down DC/DC Converter
General Description
The RT8059 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
2.8V to 5.5V. The RT8059 is ideally suited for portable
electronic devices that are powered by 1-cell Li-ion battery
or by 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 applications. The
RT8059 automatically turns off the synchronous rectifier
when the inductor current is low and enters discontinuous
PWM mode. This can increase efficiency in light load
condition.
The RT8059 enters low dropout mode when normal PWM
cannot provide regulated output voltage by continuously
turning on the upper P-MOSFET. The RT8059 enters
shutdown mode and consumes less than 0.1μA when the
EN pin is pulled low.
The switching ripple can be easily smoothed out by small
package filtering elements due to a fixed operation
frequency of 1.5MHz. This along with small 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.
Ordering Information
RT8059
Package Type
J5 : TSOT-23-5
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.
Copyright ©2011 Richtek Technology Corporation. All rights reserved.
DS8059-04 December 2011
Features
z Wide Input Voltage from 2.8V to 5.5V
z Adjustable Output from 0.6V to V_IN
z 1A Output Current
z 95% Efficiency
z No Schottky Diode Required
z 1.5MHz Fixed Frequency PWM Operation
z Small TSOT-23-5 Package
z RoHS Compliant and Halogen Free
Applications
z NIC Card
z Cellular Telephones
z Personal Information Appliances
z Wireless and DSL Modems
z MP3 Players
z Portable Instruments
Pin Configurations
(TOP VIEW)
FB
VIN
5
4
2
3
EN GND LX
TSOT-23-5
Marking Information
BQ=DNN
BQ= : Product Code
DNN : Date Code
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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