®
RT5771A
3A, 1MHz, Synchronous Step-Down Converter
General Description
The RT5771A is a high efficiency synchronous, step-down
DC-DC converter. Its input voltage ranges from 2.7V to
5.5V that provides an adjustable regulated output voltage
from 0.6V to V
IN
while delivering up to 3A of output current.
The internal synchronous low on-resistance power
switches increase efficiency and eliminate the need for
an external Schottky diode. The switching frequency is
fixed internally at 1MHz. The 100% duty cycle provides
low dropout operation, hence extending battery life in
portable systems. Current mode operation with internal
compensation allows the transient response to be
optimized over a wide range of loads and output capacitors.
The RT5771A is available in a WDFN-10L 3x3 package.
Features
High Efficiency : Up to 95%
Low R
DS(ON)
Power Switches : 69mΩ/49mΩ
Ω
Ω
Current Mode Operation
Forced-PWM (FPWM) Mode
Fast Transient Response
Fixed Frequency : 1MHz
No Schottky Diode Required
Internal Compensation
0.6V Reference Allows Low Output Voltage
Low Dropout Operation : 100% Duty Cycle
OCP, UVP, OTP
OpenVReg Type 0-LV Compliant
Ordering Information
RT5771A
Package Type
QW : WDFN-10L 3x3 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
Richtek products are :
�½
Applications
Portable Instruments
Battery Powered Equipment
Notebook Computers
Distributed Power Systems
IP Phones
Digital Cameras
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 Configuration
(TOP VIEW)
FB
VCC
VIN
GND
GND
GND
1
2
3
4
5
10
9
8
7
6
�½
Marking Information
M4= : Product Code
11
EN
PGOOD
NC
SW
SW
M4=YM
DNN
YMDNN : Date Code
WDFN-10L 3x3
Copyright
©
2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS5771A-02 June 2019
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
