![background image](http://html1.mh-extra.com/html/viewsonic/va720-2/va720-2_service-manual_1020965032.webp)
SCP time is 112.5ms
PWM Frequency about 550KHz
+25.09V
-4.95V
Max Duty=83%
R33 10K -> 0
for YV1
discharge
for power-on YV1
overshoot
Add L4 for L1
saturation in
L170E2
IAVDD
typ. 320 mA(rms)
max. 640 mA(rms)
IYV1
typ. 5mA(rms)
max.
10mA(rms)
IYVEE
typ. -5mA(rms)
max. 10mA(rms)
IV33
typ. 35mA(rms)
max. 70mA(rms)
S1
C
DC-DC(2)
QPWB-5408T8---C
Custom
3
9
03:58:10
Title
Size
Document Number
Rev
Date:
Sheet
of
OUT1
E/O3
IN-3
IN-1
E/O1
IN-2
E/O2
OUT2
OUT3
OUT1
IN-1
E/O1
OUT2
IN-2
E/O2
OUT3
E/O3
IN-3
+1.25V
+5V
+5V
AVDD_+9.6V
AVDD_+9.6V
YV1_+25.09V
AVDD_+9.6V
+5V
+5V
+5V
+1.25V
+1.25V
V+3.3V
YVEE_-4.95V
V+3.3V
C84
22u/16V
C69
4.7u/50V
R56
NC
C83
10u/16V
R57
100K
C59
22u/16V
Q5
2SC4519
1
2
3
R61
12K
D6
RB400D
R44
4.7K
U7
TPS5100
2
4
3
1
5
6
7
16
15
14
13
12
11
10
8
9
E/O2
OUT2
Vcc
IN-2
OUT3
OUT1
GND
E/O3
IN-3
IN-1
E/O1
CT/RT
DTC2
DTC1/3
SCP
Vref
R65
4.7K
R63
20K 1%
C75
2200p
R25
0
R28
0
R31
2K
C57
1u/25V
R32
14.7K 1%
L12
47uH
R29
0
NMOS
Q3
SI3434DV
1
2
3
4
5
6
D
D
G
S
D
D
R37
2.2K 1%
C67
1u/50V
R41
68K 5%
R59
7.5K 1%
C89
0.1u
C76
0.1u/25V
R45
39K 5%
R53
10K
Q4
2N7002E
1
3
2
C71
4700p/50V
R48
113K 1%
R33
NC
R42
4.7K 5%
C80
0.1u
R40
1K 1%
YV1
1
PAD
R55
1.02K 1%
C63
0.1u/25V
C73
100p
AVDD1
1
PAD
C77
0.1u
R38
4.3K 1%
R52
11K 1%
D4
RB060L-40
C93
1u
C68
0.1u/50V
U6
AIC1117-adj
3
1
2
4
INPUT
GND
OUTPUT
SINK
L10
3.3uH
R58
7.5K 1%
D5
RB400D
R51
620 1%
C70
4700p/25V
R46
0
R34
82K 1%
R43
4.7K
C192
0.1u/25V
R30
2K
C87
0.1u
Q7
DTA124TUA
1
2
3
C66
100u/25V
C72
150p
C79
10u/16V
C78
10u/16V
L11
100uH
C74
2200p
Q6
SI2303DS
1
3
2
C85
100p
C86
2200p
YVEE1
1
PAD
R35
10
Q1
SI2303DS
1
3
2
Q8
2SC3325
1
2
3
R54
4.7K
R60
10K
C92
120p
R50
0
R64
7.5K 1%
Q2
SI2303DS
1
3
2
R49
10
R47
2K
R39
0
R24
100K
C194
0.1u/25V
R26
100K
R23
51K
C193
0.1u/25V
C81
4700p
R27
47K
C90
0.22u
F2
1A
C58
0.1u/25V
C88
0.22u
R62
20K 1%
C91
1u
C60
0.1u/25V
R36
10
C82
0.1u/25V
C61
22u/25V
ViewSonic Corporation
29
Confidential – Do Not Copy
VE
7
00-1
VA720-2