G5644 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – 2.5A Buck Converter

Global Mixed-mode Technology Inc.
2.5A Buck Converter
G5644
Features
„ 4.75V to 20V Supply Voltage Operating Range
„ Fixed 500kHz Switching Frequency
„ Current-Mode Buck PWM Converter
„ Built-in P-Channel Power MOSFET
„ 2.5A Output Current
„ 0.8V Internal Reference
„ Shutdown Control
„ Thermal-Shutdown and Internal Soft Start
„ Cycle-by-Cycle Current-Limit
„ Short Circuit Protection
„ Under-Voltage Lockout Protection
„ SOP-8 Package
Applications
„ Distributed Power Systems
„ Battery Charger
„ Palmtop Computers, PDAs
„ DSL Modems
Pin Configuration
General Description
The G5644 is a high efficiency, 2.5A buck converter
with a high-side low R_DS(ON) switch. It operates from
4.75V to 20V input voltage range, and provides up to
2.5A continuous output current with the output voltage
adjustable down to 0.8V. Whenever the load is light,
the G5644 automatically change the PWM operation
mode to PFM operation to minimize the power con-
sumption. Hence it is suitable for battery-powered de-
vices.
It uses a fixed switching frequency up to 500kHz.
When a short circuit is detected on the output, the de-
vice change switching frequency to 50kHz to protect
IC from damage.
The G5644 is available in a SOP-8 package.
Ordering Information
ORDER
NUMBER
MARKING
TEMP.
RANGE
PACKAGE
(Pb free)
G5644P11U G5644 -40°C to +85°C SOP-8
Note: P1: SOP-8
1: Bonding Code
U : Tape & Reel
Typical Application Circuit
IN 1
EN 2
COMP 3
FB 4
G5644
SOP-8
8 NC
7 LX
6 GND
5 NC
V IN
5 V~18V
C_C2
opt io nal
G5644
IN
LX
10µ F
OFF _ON ^EN
COMP
FB
C_C
1.5nF
GND
R_C
20kΩ
4. 7µ H
D1
SS34 R1/3kΩ
R2/ 12 kΩ
VOUT
1V / 2. 5A
47 µF
MLCC
V IN
5 V~18V
C_C2
1 0p F
G5644
IN
LX
10µ F
OFF _ON ^EN
COMP
FB
C_C
47 0pF
GND
R_C
60kΩ
( ) ^R1
V OUT = 0 .8 V x 1 +
R2
4. 7µ H
D1
SS34 R1/3kΩ
R2/ 1 2kΩ
VOUT
1V / 2. 5A
0 .1 µF
100 µF/ 22 0µ F
Electr olytic
Ver: 0.1
Sep 05, 2008
TEL: [phone]
http://www.gmt.com.tw
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