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- 72 –
ViewSonic Corporation
Confidential - Do Not Copy
VG720
11. Schematic Diagram
11.1 Power
C709
0.1uF
R713
NC
PC5V
R709
0 1/16W
VCC3.3
VCC3.3 4
+5V
R702
51 1/16W
+
C710
100uF/25V
C
B
E
Q702
CHT2907
+
C705
1uF/16V
D701
1N4148
R720
0 1/16W
C711
0.1uF
VCC1.8 4
VCTRL 4
PC5V 3
+5V
3,4
VCC3.3 4
+5V
+5V
3,4
Title
Size
Document Number
Rev
Date:
Sheet
of
POWER
A
TSUM57AK
B
1
5
Monday , May 30, 2005
R705 4.7K 1/16W
Q701
PMBS3904
R707
4.7K 1/16W
R711
10K 1/16W
2
4
6
8
10
12
1
3
5
7
9
11
CN701
CONN
4.7K
C51
1UF
4.7K
X
X
Q4
MMBT3904
R33
4.7K
X
R29
0
R32
1UF
BL_ADJ(DC)
X
1K
0V ~ 5V
0V ~ 3.3V
R31
D C
P W M
BL_ADJ
47
C32
R31
N.C
1uF
4K7
+
C717
10uF/16V
R717
10K 1/16W
R714
10K 1/16W
R725
4.7K 1/16W
C718
0.1uF
C715
0.1uF
Q706
PMBS3904
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H3
TP
+12V
GND
Q704
AO3401L
GND
R727
10K 1/16W
GND
C701
NC
VI
3
VO
2
GN
D
1
VO
4
U701
NC/LT1117-18
+5V
+
C703
100uF/25V
+3V3
C704
NC
SOT-223
C713
0.1uF
BL_ADJ
VIN
3
ADJ
1
VOUT
2
VOUT
4
U702
AIC1084-33PM
+3V3
+5V
R723 51K
1/16W
D704
SMAL140
GND
R724 51K
GND
GND
C714
0.1uF
3
1
2
D703
BAT54C
For RSDS and Panel VCC=12V
Q707
PMBS3904
+12V
C716
0.1uF
+12V
+5V
+12V 4
Q705
AO3401L
+5V
R732
10 1/16W
R712
4.7K 1/16W
R715
NC
R710
NC
12/21 MODIFY
R706 NC
+
C719
NC/10uF/16V
R722
NC
+5V
3,4
R719
NC/10K
Q703
PMBS3904
TO-263
R701
1K 1/16W
+
C707
100uF/25V
R726 NC/4K7
D704(SSM12L) Vf=0.38V and If=1A.
So when system power on, the
system loading is about 400mA
(3.3V is about 200mA and 1.8V is
about 200mA), So D35 changed
from 1N4148(or BAT42) to
SSM12L(schottky diode).
P.S: The 1N4148 Vf=0.7V~1V can't meet
LDO spec. The BAT42, Vf is OK but the
If=200mA(forward current) can not
meet current spec.
R721
0 1/16W
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H1
TP
R716
NC
C706
0.1uF
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H2
TP
C708
1uF
R718
NC/10K
R708
10K 1/16W
R728
NC/4K7
C720
NC/0.1uF
Adj_BACKLIGHT
on_BACKLIGHT 4
on_Panel_12V
4
VLCD_12V 5
on_Panel
4
VLCD
5
VCC5V
+5V
+12V
+5V
+12V
+3V3
VLCD_12V
+5V
+5V
VLCD
+5V
+3V3
+3V3
R731
NC
+5V
R729
NC/10K
+5V
+
C712
100uF/25V
BL_ON
VCC3.3
+
C702
4.7uF/16V
Recommond to used "Blue" parts circuit
for VCC1.8V if you want to suppoert DDC
function when system power off
R704
100 1/16W
D702
1N4148
R730
0 1/16W
VCC1.8
R703
2K 1/16W
Summary of Contents for VG720 - 17" LCD Monitor
Page 37: ...37 ViewSonic Corporation Confidential Do Not Copy VG720 Sep2 Inpute the S N and execute Enter...
Page 38: ...38 ViewSonic Corporation Confidential Do Not Copy VG720...
Page 39: ...39 ViewSonic Corporation Confidential Do Not Copy VG720 Sep3 Key the Enter and write the data...
Page 41: ...41 ViewSonic Corporation Confidential Do Not Copy VG720 5 7 Packing For Shipping...
Page 43: ...43 ViewSonic Corporation Confidential Do Not Copy VG720 6 Troubleshooting Flow Chart...
Page 62: ...62 ViewSonic Corporation Confidential Do Not Copy VG720...
Page 63: ...63 ViewSonic Corporation Confidential Do Not Copy VG720...
Page 80: ...80 ViewSonic Corporation Confidential Do Not Copy VG720 12 2 MAIN BOARD PCB BUTTON VIEW...
Page 82: ...82 ViewSonic Corporation Confidential Do Not Copy VG720 12 5 POWER PCB TOP VIEW...
Page 83: ...83 ViewSonic Corporation Confidential Do Not Copy VG720 12 6 POWER PCB BUTTON VIEW...
Page 84: ...84 ViewSonic Corporation Confidential Do Not Copy VG720 12 6 AUDIO PCB TOP VIEW...
Page 85: ...85 ViewSonic Corporation Confidential Do Not Copy VG720 12 6 AUDIO PCB BUTTON VIEW...