RT7297B
®
DS7297B-02 September 2012
www.richtek.com
1
©
Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
Ordering Information
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.
Pin Configurations
(TOP VIEW)
Applications
Wireless AP/Router
Set-Top-Box
Industrial and Commercial Low Power Systems
LCD Monitors and TVs
Green Electronics/Appliances
Point of Load Regulation of High-Performance DSPs
SOP-8 (Exposed Pad)
3A, 18V, 1.2MHz Synchronous Step-Down Converter
General Description
The RT7297B 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
RT7297B'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 RT7297B also provides under voltage
protection and thermal shutdown protection. The low
current (<3
μ
A) shutdown mode provides output
disconnection, enabling easy power management in
battery-powered systems. The RT7297B is available in
an SOP-8 (Exposed Pad) package.
Features
±±±±±
1.5% High Accuracy Reference Voltage
4.5V to 18V Input Voltage Range
3A Output Current
Integrated N-MOSFET Switches
Current Mode Control
Fixed Frequency Operation : 1.2MHz
Output Adjustable from 0.8V to 12V
Up to 95% Efficiency
Programmable Soft-Start
Stable with Low ESR Ceramic Output Capacitors
Cycle-by-Cycle Over Current Protection
Input Under Voltage Lockout
Output Under Voltage Protection
Thermal Shutdown Protection
RoHS Compliant and Halogen Free
BOOT
VIN
SW
GND
SS
EN
FB
COMP
GND
2
3
4
5
6
7
8
9
Package Type
SP : SOP-8 (Exposed Pad-Option 1)
RT7297B
Lead Plating System
Z : ECO (Ecological Element with
Halogen Free and Pb free)
H : UVP Hiccup
L : UVP Latch-Off
Marking Information
RT7297BxZSP : Product Number
x : H or L
YMDNN : Date Code
RT7297Bx
ZSPYMDNN
