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10. Schematic Diagram
ViewSonic Corporation
Confidential - Do Not Copy
VA503b-1_ VA503m-1
68
Model
Title
Date
Rev:
ViewSonic Corporation
POWER
+12V
+12V
+5V
GND
+5V
GND
GND
BL_ON
BL_ADJ
GND
GND
GND
on_Panel
4
VLCD_12V 5
on_Panel_12V
4
VLCD 5
VCTRL 4
VCC1.8 4
VCC3.3 4
on_BACKLIGHT 4
+3V3
+5V
3,4
+12V 4
VCC3.3 4
+5V
3,4
PC5V 3
+5V
3,4
Adj_BACKLIGHT
+5V
+12V
+5V
VLCD_12V
+3V3
+5V
VLCD
+3V3
+3V3
VCC3.3
VCC1.8
+5V
+3V3
+12V
+5V
PC5V
VCC3.3
+5V
+12V
+5V
+5V
+5V
+5V
+5V
VCC5V
C51
4.7K
4.7K
1UF
R33
MMBT3904
Q4
X
X
4.7K
1UF
R32
0
R29
X
1K
X
BL_ADJ(DC)
0V ~ 3.3V
0V ~ 5V
R31
BL_ADJ
P W M
D C
N.C
R31
C32
47
1uF
4K7
12/21 MODIFY
TO-263
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.
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).
R117
NC
R117
NC
C708
1uF
C708
1uF
R726 NC/4K7
R726 NC/4K7
C?
NC
C?
NC
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H2
TP
H2
TP
R?
51K
R?
51K
R731
NC
R731
NC
R?
0 1/16W
R?
0 1/16W
C711
0.1uF
C711
0.1uF
R725
4.7K 1/16W
R725
4.7K 1/16W
R?
2K 1/16W
R?
2K 1/16W
+
C712
100uF/25V
+
C712
100uF/25V
R?
0 1/16W
R?
0 1/16W
C716
0.1uF
C716
0.1uF
R730
0 1/16W
R730
0 1/16W
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H3
TP
H3
TP
R?
51 1/16W
R?
51 1/16W
R?
100 1/16W
R?
100 1/16W
+
C?
1uF/16V
+
C?
1uF/16V
+
C710
100uF/25V
+
C710
100uF/25V
D?
1N4148
D?
1N4148
+
C?
4.7uF/16V
+
C?
4.7uF/16V
R706 NC
R706 NC
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
H3
TP
H3
TP
R118
NC
R118
NC
Q705
AO3401L
Q705
AO3401L
R705 4.7K 1/16W
R705 4.7K 1/16W
R52
NC
R52
NC
+
C707
100uF/25V
+
C707
100uF/25V
R732
10 1/16W
R732
10 1/16W
R43
10K 1/16W
R43
10K 1/16W
R46
4.7K 1/16W
R46
4.7K 1/16W
Q707
PMBS3904
Q707
PMBS3904
R711
10K 1/16W
R711
10K 1/16W
R49
NC/10K
R49
NC/10K
R?
51K 1/16W
R?
51K 1/16W
R707
4.7K 1/16W
R707
4.7K 1/16W
Q704
AO3401L
Q704
AO3401L
+
C39
NC/10uF/16V
+
C39
NC/10uF/16V
C?
NC
C?
NC
R?
NC
R?
NC
C
B
E
Q?
CHT2907
Q?
CHT2907
C709
0.1uF
C709
0.1uF
+
C717
10uF/16V
+
C717
10uF/16V
C49
0.1uF
C49
0.1uF
C718
0.1uF
C718
0.1uF
R44
NC
R44
NC
C713
0.1uF
C713
0.1uF
R51
0 1/16W
R51
0 1/16W
VIN
3
ADJ
1
VOUT
2
VOUT
4
U702
AIC1084-33PM
U702
AIC1084-33PM
2
4
6
8
10
12
1
3
5
7
9
11
CN701
CONN
CN701
CONN
C714
0.1uF
C714
0.1uF
Q701
PMBS3904
Q701
PMBS3904
R56
NC/4K7
R56
NC/4K7
VI
3
VO
2
GN
D
1
VO
4
U?
NC/LT1117-18
U?
NC/LT1117-18
D704
SMAL140
D704
SMAL140
C715
0.1uF
C715
0.1uF
C40
NC/0.1uF
C40
NC/0.1uF
R701
1K 1/16W
R701
1K 1/16W
3
1
2
D6
BAT54C
D6
BAT54C
R719
NC/10K
R719
NC/10K
R717
10K 1/16W
R717
10K 1/16W
R727
10K 1/16W
R727
10K 1/16W
+
C?
100uF/16V
+
C?
100uF/16V
D?
1N4148
D?
1N4148
Q703
PMBS3904
Q703
PMBS3904
R729
NC/10K
R729
NC/10K
Q706
PMBS3904
Q706
PMBS3904
Summary of Contents for VA503b-1
Page 25: ...Circuit Diagram ViewSonic Corporation VA503b 1_ VA503m 1 22 Confidential Do Not Copy...
Page 44: ...ViewSonic Corporation VA503b 1_ VA503m 1 41 Confidential Do Not Copy...
Page 51: ...Picture 17 ViewSonic Corporation VA503b 1_ VA503m 1 48 Confidential Do Not Copy...
Page 63: ...ViewSonic Corporation VA503b 1_ VA503m 1 60 VA503m Confidential Do Not Copy...
Page 78: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 75 11 PCB Layout Diagram...
Page 79: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 76...
Page 81: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 78 POWER PCB VIEW...
Page 82: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 79...