High-Speed Step-Down Controller

G5338
Global Mixed-mode Technology
High-Speed Step-Down Controller
Features
General Description
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G5338 uses constant on-time control scheme to handle wide input/output voltage ratios with ease and provides 100ns “instant-on” response to load transients
while maintaining a relatively constant switching frequency. The G5338 achieves high efficiency at a reduced cost by eliminating the current-sense resistor
found in traditional current-mode PWMs. Efficiency is
further enhanced by an ability to drive very large synchronous rectifier MOSFETs. Single-stage buck conversion allows these devices to directly step down
high-voltage batteries for the highest possible efficiency. The noiseless pulse-skipping mode setting
maintains the switching frequency above 25kHz to
eliminates the audio noise. The G5338 is intended for
CPU core, chipset, DRAM, or other low-voltage supplies as low as 0.5V. The G5338 is available in
TQFN2X2-12 package.
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Ultra-High Efficiency
4700ppm/°C RDS(ON) Current Sensing ( without
Current-Sense Resistor )
Quasi-PWM with 100ns Load-Step Response
Built in 1% 0.5V Reference Voltage
0.5V to 3.3V Adjustable Output Range
4.5V to 28V Battery Input Range
Integrated Boost Diode
OVP & UVP
1.5ms Voltage Servo Soft-Start
Drives Large Synchronous-Rectifier FETs
Power-Good Indicator
Thermal Shutdown (Non-latch)
Applications
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Notebook Computers
CPU Core Supply
„ I/O Supply
„ Chipset/RAM Supply as Low as 0.5V
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Ordering Information
ORDER
NUMBER
MARKING
TEMP.
RANGE
PACKAGE
(Green)
G5338K71U
5338
-40°C to +85°C
TQFN2X2-12
Note: K7: TQFN2X2-12
1: Bonding Code
U : Tape & Reel
TON
ILIM
11
10
12
GND
Pin Configuration
2
Thermal
Pad
8
EN
DH
3
7
MODE
6
LX
FB
PGOOD
5
9
VCC
13 GND
4
1
BST
DL
G5338 TQFN2X2-12
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.4
May 03, 2012
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