®
RT7251A/B
1.5A, 17V, 340/800kHz Synchronous Step-Down Converter
General Description
The RT7251A/B is a high efficiency, monolithic
synchronous step-down DC/DC converter that can operate
at 340kHz/800kHz, while delivering up to 1.5A output
current from a 4V to 17V input supply. The RT7251A/B's
current mode architecture allows the transient response
to be optimized. Cycle-by-cycle current limit provides
protection against shorted outputs and soft-start eliminates
input current surge during start-up. Fault conditions also
include output under voltage protection, output over voltage
protection and thermal shutdown. The low current (<5μA)
shutdown mode provides output disconnection, enabling
easy power management in battery-powered systems. The
RT7251A/B is available in a WDFN-8L 2x2 package.
Features
4V to 17V Input Voltage Range
1.5A Output Current
Internal N-MOSFETs
Current Mode Control
Fixed Frequency Operation : 340kHz/800kHz
Output Adjustable from 0.8V to 12V
Up to 95% Efficiency
Internal Compensation
Stable with Low ESR Ceramic Output Capacitors
Cycle-by-Cycle Over Current Protection
Input Under Voltage Lockout
Output Under Voltage Protection
Output Over Voltage Protection
Power Good Indicator
Thermal Shutdown Protection
RoHS Compliant and Halogen Free
Ordering Information
RT7251A/B
Package Type
QW : WDFN-8L 2x2 (W-Type)
Lead Plating System
Z : ECO (Ecological Element with
Halogen Free and Pb free)
A : 340kHz
B : 800kHz
Applications
Industrial and Commercial Low Power Systems
Computer Peripherals
LCD Monitors and TVs
Green Electronics/Appliances
Point of Load Regulation for High-Performance DSPs,
FPGAs, and ASICs
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)
SW
VIN
BOOT
EN
1
2
3
4
8
7
6
5
Marking Information
RT7251AZQW
03 : Product Code
W : Date Code
9
GND
GND
PGOOD
FB
WDFN-8L 2x2
03W
RT7251BZQW
70 : Product Code
70W
W : Date Code
Copyright
©
2012 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7251A/B-01 April 2012
GND
www.richtek.com
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