RT7257C Datasheet, PDF (1/14 Pages) Richtek Technology Corporation – 3A, 18V, 340kHz Synchronous Step-Down Converter

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RT7257C
3A, 18V, 340kHz Synchronous Step-Down Converter
General Description
The RT7257C 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
RT7257C'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 RT7257C 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 RT7257C is available in
an SOP-8 (Exposed Pad) package.
Ordering Information
RT7257C
Package Type
SP : SOP-8 (Exposed Pad-Option 2)
Lead Plating System
Z : ECO (Ecological Element with
Halogen Free and Pb free)
H : UVP Hiccup
L : UVP Latch-Off
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.
Marking Information
RT7257Cx
ZSPYMDNN
RT7257CxZSP : Product Number
x : H or L
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
Pin Configurations
(TOP VIEW)
BOOT
VIN
SW
GND
8
2
7
GND
3
6
9
4
5
SS
EN
COMP
FB
SOP-8 (Exposed Pad)
Copyright ©2012 Richtek Technology Corporation. All rights reserved.
DS7257C-02 September 2012
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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