®
RT7258
8A, 24V, 600kHz Step-Down Converter with Synchronous
Gate Driver
General Description
The RT7258 is a synchronous step-down DC/DC converter
with an integrated high side internal power MOSFET and
a gate driver for a low side external power MOSFET. It
can deliver up to
8A
output current from a 4.5V to 24V
input supply. The RT7258's current mode architecture
allows the transient response to be optimized over a wider
input voltage and load range. Cycle-by-cycle current limit
provides protection against shorted outputs and soft-start
eliminates input current surge during start-up. The RT7258
is synchronizable to an external clock with frequency
ranging from 300kHz to 1.5MHz.
The RT7258 is available in WDFN-14L 4x3 and SOP-8
(Exposed Pad) packages.
Features
4.5V to 24V Input Voltage Range
8A
Output Current
45mΩ Internal High Side N-MOSFET
Ω
Current Mode Control
600kHz Switching
Frequency
Adjustable Output from 0.808V to 15V
Up to 95% Efficiency
Internal Compensation
Stable with Ceramic Capacitors
Synchronous External Clock : 300kHz to 1.5MHz
Cycle-by-Cycle Current Limit
Input Under Voltage Lockout
Output Under Voltage Protection
Power Good Indicator
Thermal Shutdown Protection
RoHS Compliant and Halogen Free
Applications
Point of Load Regulator in Distributed Power System
Digital Set top Boxes
Personal Digital Recorders
Broadband Communications
Flat Panel TVs and Monitors
Simplified Application Circuit
RT7258
BOOT
C
BOOT
SW
VCC
C
VCC
Power Good
Chip Enable
EN/SYNC
GND
PGOOD
FB
R2
BG
Q1
R1
C
OUT
L
V
OUT
V
IN
C
IN
VIN
Copyright
©
2012 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7258-00 January 2012
www.richtek.com
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RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
