G5312 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – High Efficiency 8A Synchronous Buck Converter

Global Mixed-mode Technology
G5312
High Efficiency 8A Synchronous Buck Converter
Features
„ Ultra-High Efficiency
„ Integrated 20mΩ at Vcc=5V N-Channel MOSFET
for Low Side
„ Integrated 20mΩ at Vcc=5V N-Channel
MOSFET for High Side
„ No Current-Sense Resistor (Lossless I_LIMIT)
„ Quasi-PWM with 100ns Load-Step Response
„ 1% VOUT Accuracy Over Line and Load
„ Programmable Switching Frequency
„ Adjustable Output Range from 0.75V
„ 4.5V to 28V Adapter or Battery Input Range
„ Integrated Boost Switch
„ OVP & UVP
„ Over Temperature Protection (non-latch)
„ 3.3ms Soft-Start
„ Power-Good Indicator
„ Fixed 5V, 20mA Linear Regulator
Applications
„ LCD Monitor/LCD TV
„ Notebook Computers
„ I/O Supply
„ Chipset/RAM Supply as Low as 0.75V
„ Networking Power Supply
Ordering Information
ORDER
NUMBER
G5312QN1U
G5312QN2U
Note:QN: QFN4X4-28
1 & 2: Leadframe Code
U : Tape & Reel
MARKING
5312
5312
Pin Configuration
General Description
G5312 is a 8A, synchronous DC/DC buck converter
with integrated 20mΩ N-channel high-side MOSFET
and 20mΩ N-channel low-side MOSFET. It uses con-
stant on-time control scheme to handle wide in-
put/output voltage ratios with ease and provides 100ns
“instant-on” response to load transients while main-
taining a relatively constant switching frequency. The
G5312 achieves high efficiency at a reduced cost by
eliminating the current-sense resistor found in tradi-
tional current-mode PWMs. Single-stage buck conver-
sion allows these devices to directly step down
high-voltage batteries for the highest possible effi-
ciency. The built-in 5V LDO supports 20mA for internal
circuits. The G5312 is intended for the main power
supply of LCD TV, Notebook Computer, or other
low-voltage supplies as low as 0.75V. The G5312 is
available in QFN4X4-28 package.
TEMP.
RANGE
-40°C to +85°C
-40°C to +85°C
PACKAGE
(Green)
QFN4X4-28
QFN4X4-28
ILIM 1
20 V+
AGND 2
V5V 3
AGND
19 V+
V+
18 V+
PGND 4
17 V+
LX 5
LX 6
LX
LX 7
LX 8
ILIM 1
AGND 2
V5V 3
PGND 4
LX 5
LX 6
LX 7
LX 8
AGND
V+
LX
20 V+
19 V+
18 V+
17 V+
Ver: 1.1
Oct 21, 2013
G5312QN1U QFN4X4-28
G5312QN2U QFN4X4-28
Note: Recommend connecting the Thermal Pad to the Ground for excellent power dissipation.
TEL: [phone]
http://www.gmt.com.tw
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