智 新
Preliminary
RT7257E
SacPower
3A, 17V, 340kHz Synchronous Step-Down Converter
General Description
Features
z
1.5% High Accuracy Feedback Voltage
The RT7257E is a high efficiency, monolithic synchronous
step-down DC/DC converter that can deliver up to 3A
output current from a 4.5V to 17V input supply. The
RT7257E's current mode architecture and external
compensation allow the transient response to be
optimized over a wide range of loads and output capacitors.
Cycle-by-cycle current limit provides protection against
shorted outputs, and soft-start eliminates input current
surge during start-up. The RT7257E provides thermal
shutdown protection. The low current (<3μA) shutdown
mode provides output disconnection, enabling easy power
management in battery-powered systems. The RT7257E
is available in an SOP-8 (Exposed Pad) package.
z 4.5V to 17V 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 Up to 95% Efficiency
z Programmable Soft-Start
z Stable with Low ESR Ceramic Output Capacitors
z Cycle-by-Cycle Over Current Protection
z Input Under Voltage Lockout
z Thermal Shutdown Protection
z RoHS Compliant and Halogen Free
Ordering Information
RT7257EN
Applications
z Wireless AP/Router
Package Type
SP : SOP-8 (Exposed Pad-Option 2)
z Set-Top-Box
z Industrial and Commercial Low Power Systems
z LCDMonitors and TVs
Lead Plating System
Z : ECO (Ecological Element with
Halogen Free and Pb free)
z Green Electronics/Appliances
z Point of Load Regulation of High-PerformanceDSPs
Note :
Richtek products are :
Pin Configurations
` 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.
(TOP VIEW)
8
BOOT
VIN
SS
2
3
4
7
6
5
EN
GND
SW
COMP
FB
9
GND
Marking Information
SOP-8 (Exposed Pad)
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
http//www.sacpower.net
1
E-mail:nikozhong@hotmail.com
0755-83983280
系人: 先生