uP1728S
1.2MHz, 3.0A, High-Efficiency
Synchronous-Rectified Buck Converter
Features
General Description
The uP1728S is a high efficiency synchronous-rectified
buck converter with internal power switches. Fixed 1.2MHz
PWM operation allows possible smallest output ripple and
external component size. With high conversion efficiency
and small package, the uP1728S is ideally suitable for
portable devices and USB/PCIE-based interface cards,
where PCB area is especially concerned.
2.6V to 5.5V Input Voltage Range
Adjustable Output from 0.6V to VIN
Guaranteed 3.0A Output Current
+
Accurate Reference: 0.6V ( 1%)
Up to 95% Conversion Efficiency
Low Quiescent Current
With internal low RDS(ON) switches, the uP1728S is capable
of delivering 3.0Aoutput current over a wide input voltage
range from 2.6V to 5.5V. The output voltage is adjustable
from 0.6V to VIN by a voltage divider.
Integrated Low RDS(ON) Upper and Lower MOSFET
Switches: 80mΩ and 60mΩ
Current Mode PWM Operation
Fixed Frequency : 1.2MHz
Other features include internal soft-start, chip enable, over-
voltage, under-voltage, over-temperature and over-current
protections. The uP1728S is available in a space-saving
WDFN3x3-10L package.
100% Maximum Duty Cycle for Lowest Dropout
Internal Soft-Start
Over Voltage and Under Voltage Protection
Over Temperature and Over Current Protection
WDFN3x3-10L Package
Ordering Information
Order Number
uP1728SDDA
Package Type
WDFN3x3-10L
Top Marking
uP1728S
RoHS Compliant and Halogen Free
Applications
Note:
Battery-Powered Portable Devices
(1) Please check the sample/production availability with
uPI representatives.
MP3 Players
(2) uPI products are compatible with the current IPC/JEDEC
J-STD-020 requirement. They are halogen-free, RoHS
compliant and 100% matte tin (Sn) plating that are suitable
for use in SnPb or Pb-free soldering processes.
Notebook Computers
Wireless and DSL Modems
Personal Information Appliances
IP Phones
Pin Configuration
Digital Cameras
1
2
3
4
5
10 EN
FB
VDD
VIN
802.11 WLAN Power Supplies
FPGA/ASIC Power Supplies
POK
9
8
7
6
GND
MODE
LX
Dynamically Adjustable Power Supply for
CDMA/WCDMA Power Amplifiers
GND
GND
LX
USB-Based xDSL Modems and Other Network
Interface Cards
WDFN3x3-10L
Point-of-Load Regulation
uP1728S-DS-F00A0, Mar. 2018
www.upi-semi.com
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