®
RT8120
Single-Phase Synchronous Buck PWM Controller
General Description
Features
z Wide Input Voltage Range : 3V to 13.2V
z Embedded Switching Boot Diode
z 0.8V 1%, 0.6V 1.5% Internal Reference
z Shoot-Through Protection and Short Pulse Free
Technology for Gate Drivers
The RT8120 is a single-phase synchronous buck PWM
DC/DC controller designed to drive two N-MOSFET. It
provides a highly accurate, programmable output voltage
precisely regulated to low voltage requirements with an
internal 0.8V 1% ( option for 0.6V 1.5%) reference. The
RT8120 uses a single feedback loop voltage mode PWM
control for fast transient response.An oscillator with fixed
frequency 300kHz reduces the external inductor and
capacitor component size for saving PCB board area. The
RT8120 provides fast transient response to satisfy high
current output applications while minimizing external
components. It is suitable for high performance graphic
processors,DDR and VTTpower. The RT8120 incorporates
an externally compensated error amplifier and an internal
soft-start and output enable. The RT8120 comes in
SOP-8 and SOP-8 (Exposed Pad) packages.
z Fixed Frequency 300kHz
z Internal Soft-Start
z Over Current Protection by Sensing MOSFET RDS(ON)
z Enable/Shutdown Control
z Drives Two N-MOSFETs
z Full Duty Cycle : 0% to 85%
z Fast Transient Response
z Voltage Mode PWM Control with External
Feedback Loop Compensation
z Pinless LGATE Over Current Setting (LGOCS)
z Under Voltage Protection
z SOP-8 and SOP-8 (Exposed Pad) Packages
z RoHS Compliant and Halogen Free
Ordering Information
RT8120
Applications
Package Type
S : SOP-8
SP : SOP-8 (Exposed-Pad-Option 1)
z System (Graphic, MB) with 5V or 12V Power
z Graphic Cards (AGP 8X, 4X, PCI Express*16)
z 3.3V to 12V Input DC/DC Regulators
Lead Plating System
z Low VoltageDistributed Power Supplies
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)
Pin Configurations
Reference Voltage
A/C : 0.6V
(TOP VIEW)
B/D : 0.8V
8
BOOT
UGATE
PHASE
COMP/EN
FB
2
3
4
7
6
5
Note :
GND
Richtek products are :
LGATE/OCSET
VCC
` 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.
SOP-8
8
7
6
5
BOOT
UGATE
PHASE
COMP/EN
FB
2
3
4
GND
GND
9
LGATE/OCSET
VCC
SOP-8 (Exposed Pad)
Copyright 2013 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS8120-08 September 2013
www.richtek.com
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