G5172 Datasheet, PDF (1/2 Pages) Global Mixed-mode Technology Inc – High Efficiency, 4A Output, Synchronous Step Down

Global Mixed-mode Technology
G5172
High Efficiency, 4A Output, Synchronous Step Down
Features
„ Two 30mΩ (typical) MOSFETs for high effi-
ciency at 4A loads
„ 200kHz to 2MHz Switching Frequency
„ 0.8V ± 1% Voltage Reference Over Temperature
„ Synchronizes to External Clock
„ Adjustable Soft Start
„ UV and OV Power Good Output
„ Low Operating and Shutdown Quiescent Cur-
rent
„ Safe Start-up into Pre-Biased Output
„ Cycle by Cycle Current Limit, Thermal and Fre-
quency Fold Back Protection
„ Thermally Enhanced 3mm × 3mm 16-pin QFN
and 4mm × 4mm 16-pin QFN
„ Package QFN4x4 Loads can attain to 5A
Applications
„ Low-Voltage, High-Density Power Systems
„ Point of Load Regulation for High Performance
DSPs, FPGAs, ASICs and Microprocessors
„ Broadband, Networking and Optical Commu-
nication Infrastructure
Ordering Information
ORDER _Marking
NUMBER
TEMP.
RANGE
PACKAGE
(Green)
G5172R41U
5172
-40°C to +85°C TQFN3X3-16
G5172R41D
5172
-40°C to +85°C TQFN3X3-16
G5172R81U
5172
-40°C to +85°C TQFN4X4-16
Note: R4: TQFN3X3-16 R8:TQFN4X4-16
1: Bonding Code
U & D: Tape & Reel
Pin Configuration
General Description
The G5172 device is a full featured 6.0V, 4A synchro-
nous step down current mode converter with two inte-
grated MOSFETs.
The G5172 enables small designs by integrating the
MOSFETs, implementing current mode control to re-
duce external component count, reducing inductor size
by enabling up to 2MHz switching frequency, and
minimizing the IC footprint with a small 3mm x 3mm
(4mm x 4mm) thermally enhanced QFN package.
The G5172 provides accurate regulation for a variety
of loads with an accurate ±1% Voltage Reference
(VREF) over temperature.
Efficiency is maximized through the integrated 30mΩ
MOSFETs and 350µA typical supply current. Using the
enable pin, shutdown supply current is reduced to 2µA
by entering a shutdown mode.
Under voltage lockout is internally set at 2.6V, but can
be increased by programming the threshold with a
resistor network on the enable pin. The output voltage
startup ramp is controlled by the soft start pin. An open
drain power good signal indicates the output is within
93% to 107% of its nominal voltage.
Frequency fold back and thermal shutdown protects
the device during an over-current condition.
Typical Application Circuit
G5172
VINA 1
VIN 2
GND 3
GND 4
Thermal
Pad
12 LX
11 LX
10 LX
9 SS
TQFN3X3-16/TQFN4X4-16
Note: Recommend connecting the Thermal Pad to
the Ground for excellent power dissipation.
VIN
3.3V to 6.0V
R5
100KΩ
R3
48.7KΩ
CI
10µF
R4
32.4KΩ
C2
0.1µF
G5172
VIN
EN
BS
CBS
0.1µF
LX
FB
PG
(0.803V)
CSS
0.01µF
RT
182KΩ
CZ*
SS
RT
COMP
RC
20KΩ
CC
470PF
GND
AGND
EP
LO
1.0µH
CO
22*2µF
＊ Option
＊ VINA must connect to VIN
VOUT
1.8V
CD*
R1
100KΩ
R2
80KΩ
Ver: 0.9
Jul 18, 2012
TEL: [phone]
http://www.gmt.com.tw
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