G5173 Datasheet. Www.s Manuals.com. Gmt
User Manual: Marking of electronic components, SMD Codes 51, 51**, 51***, 5103, 51031, 5108, 51117, 51123, 51123A, 51125, 5121*, 51216, 51219, 5121M, 51225, 5160x, 51716, 5173, 5193, 5198NL, 5199NL, 51A, 51AC30B, 51AC33, 51AC33B, 51Y. Datasheets 1.5SMC51AT3, AT5160TP1U, BZV49-C51, CS51031, FX011Z, G5108RDU, G5111T11, G5121TB1U, G5173R41U, G5193R41U, KB4312B-GRE, LP2951ACSDX-3.3, LP2951CSD-3.0, LP2951CSD-3.3, MM5Z2V7, MTP5103N3, PJ5121EMR, PJ5121EQFN, SST5198NL, SST5199NL, TPS51117PW, TPS51117RGY, TPS51123ARGER, TPS51123
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Ver: 0.5
Nov 17, 2010
TEL: 886-3-5788833
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1
G5173
Global Mixed-mode Technology Inc.
High Efficiency, 3A Output, Synchronous Step Down
Features
Two 45mΩ (typical) MOSFETs for high effi-
ciency at 3A loads
300kHz to 2MHz Switching Frequency
0.827V±3% Voltage Reference Over Tempera-
ture
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
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
NUMBER Marking TEMP.
RANGE
PACKAGE
(Green)
G5173R41U 5173 -40°C to +85°C TQFN3X3-16
G5173R41D 5173 -40°C to +85°C TQFN3X3-16
Note: R4: TQFN3X3-16
1: Bonding Code
U & D: Tape & Reel
General Description
The G5173 device is a full featured 5.5V, 3A synchro-
nous step down current mode converter with two inte-
grated MOSFETs.
The G5173 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
thermally enhanced QFN package.
The G5173 provides accurate regulation for a variety
of loads with an accurate ±3% Voltage Reference
(VREF) over temperature.
Efficiency is maximized through the integrated 45mΩ
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.
Pin Configuration Typical Application Circuit
G5173 TQFN3X3-16
COMP
1
2
3
4
12
11
10
9
LX
LX
LX
SS
16
15
14
13
RT
AGND
FB
Thermal
Pad
PG
BS
EN
VIN
VINA
VIN
GND
GND
5
6
7
8
Note: Recommend connecting the Thermal Pad to
the Ground for excellent power dissipation.
VIN
3.3V to 5.5V
C
I
10µF
R3
48.7KΩ
R4
32.4KΩ
C
SS
0.01µF
R
T
182KΩ
G5173
R
C
20KΩ
C
C
470PF
VINA
VIN
EN
RT
COMP
SS
BS
LX
FB
(0.827V)
GND
AGND
EP
C
BS
0.1µF
L
O
1.0µH VOUT
1.8V
C
D
*
C
O
22*2µF R1
100KΩ
R2
80KΩ
C
Z
*
＊Option
R5
100KΩ
PG
＊VINA must connect to VIN
G5173 TQFN3X3-16
COMP
1
2
3
4
12
11
10
9
LX
LX
LX
SS
16
15
14
13
RT
AGND
FB
Thermal
Pad
PG
BS
EN
VIN
VINA
VIN
GND
GND
5
6
7
8
Note: Recommend connecting the Thermal Pad to
the Ground for excellent power dissipation.
VIN
3.3V to 5.5V
C
I
10µF
R3
48.7KΩ
R4
32.4KΩ
C
SS
0.01µF
R
T
182KΩ
G5173
R
C
20KΩ
C
C
470PF
VINA
VIN
EN
RT
COMP
SS
BS
LX
FB
(0.827V)
GND
AGND
EP
C
BS
0.1µF
L
O
1.0µH VOUT
1.8V
C
D
*
C
O
22*2µF R1
100KΩ
R2
80KΩ
C
Z
*
＊Option
R5
100KΩ
PG
＊VINA must connect to VIN
