G5728 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – 1MHz 1A Synchronous Step-Down Regulator

Global Mixed-mode Technology
G5728
1MHz 1A Synchronous Step-Down Regulator
Features
„ High Efficiency: Up to 93%
„ Low Quiescent Current: Only 50µA During Op-
eration
„ Internal Soft Start Function
„ 1A Output Current
„ 2.5V to 6V Input Voltage Range
„ 1MHz Switching Frequency
„ No Schottky Diode Required
„ 100% Duty Cycle in Dropout Operation
„ 0.6V Reference Allows Low Output Voltages
„ <1µA Shutdown Current
„ Current Mode Operation for Excellent Line and
Load Transient Response
„ Over Temperature Protected
„ RoHS Compliant
General Description
The G5728 is a high efficiency monolithic synchronous
buck regulator using a constant frequency, current
mode architecture. Supply current during operation is
only 50µA and drops to <1µA in shutdown. The 2.5V
to 6V input voltage range makes the G5728 ideally
suited for single Li-Ion battery-powered applications.
100% duty cycle provides low dropout operation, ex-
tending battery run time in portable systems. Switching
frequency is internally set at 1MHz, allowing the use of
small surface mount inductors and capacitors. The
internal synchronous switch increase efficiency and
eliminates the need for an external Schottky diode.
Built-in soft start function eliminates in-rush current
that could damage the system.
Applications
„ Cellular Telephones
„ Personal Information Appliances
„ Microprocessors and DSP Core Supplies
„ Wireless and DSL Modems
„ Digital Still and Video Cameras
„ MP3 Players
„ Portable Instruments
Ordering Information
ORDER
NUMBER
MARKING
G5728TO1U
5728x
G5728T11U
Note: TO:TSOT-23-5
1: Bonding Code
U: Tape & Reel
5728x
T1:SOT-23-5
OUTPUT
VOLTAGE
Adjustable
Adjustable
TEMP.
RANGE
-40°C~ +85°C
-40°C~ +85°C
PACKAGE
(Green)
TSOT-23-5
SOT-23-5
Pin Configuration
Typical Application Circuit
EN 1
G5728
5 VFB
GND 2
LX 3
4 VIN
TSOT-23-5/SOT-23-5
V_IN
4~6V
G5728
4
VIN
3
LX
C_IN
2.2µF
CER
1
EN
5
VFB
GND
2
R1
V_OUT = 0.6V × (1+ _R2 )
2.2µH
C_FB* (option)
R1
R2 82k
18k
V_OUT
3.3V
300mA
C_OUT
10µF
CER
Ver: 1.1
May 27, 2013
TEL: [phone]
http://www.gmt.com.tw
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