RT7257J Datasheet, PDF (1/15 Pages) Richtek Technology Corporation – 3A, 18V, 340kHz Synchronous Step-Down Converter

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RT7257J
3A, 18V, 340kHz Synchronous Step-Down Converter
General Description
The RT7257J is a high efficiency, monolithic synchronous
step-down DC/DC converter that can deliver up to 3A
output current from a 4.5V to 18V input supply. The
RT7257J's current mode architecture and external
compensation allow the transient response to be
optimized over a wide input voltage range and loads.
Cycle-by-cycle current limit provides protection against
shorted outputs, and soft-start eliminates input current
surge during start-up. The RT7257J also provides under
voltage protection and thermal shutdown protection. The
low current (<3μA) shutdown mode provides output
disconnection, enabling easy power management in
battery-powered systems. The RT7257J is available in an
SOP-8 (Exposed Pad) package.
Marking Information
RT7257JCHZSP : Product Number
RT7257JCH
ZSPYMDNN
YMDNN : Date Code
Features
z ±1.5% High Accuracy Reference Voltage
z 4.5V to 18V Input Voltage Range
z 3A Output Current
z Integrated N-MOSFET Switches
z Current Mode Control
z Fixed Frequency Operation : 340kHz
z Output Adjustable from 0.8V to 15V
z Stable with Low ESR Ceramic Output Capacitors
z Up to 95% Efficiency
z Programmable Soft-Start
z Cycle-by-Cycle Over Current Protection
z Input Under Voltage Lockout
z Output Under Voltage Protection
z Thermal Shutdown Protection
z RoHS Compliant and Halogen Free
Applications
z Wireless AP/Router
z Set-Top-Box
z Industrial and Commercial Low Power Systems
z LCD Monitors and TVs
z Green Electronics/Appliances
z Point of Load Regulation of High-Performance DSPs
Simplified Application Circuit
V_IN
C_IN
Chip Enable
C_SS
VIN
BOOT
RT7257J
SW
EN
SS
FB
GND
COMP
C_{BOOT L}
V_OUT
C_{C RC}
R1
C_OUT
R2
C_P
Open
Copyright ©2012 Richtek Technology Corporation. All rights reserved.
DS7257J-02 September 2012
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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