BBK DV721S, Service Manual, Page: 24 / 41

K4
0
4
K4
0
3
K4
0
1
K4
0
2
1 2
VD4
0
1
1N
4148
K4
0
5
K4
0
6
P1/S1
1
P2/S2
2
P3/S3
3
P4/S4
4
S5
5
S6
6
S7
7
S8
8
S9
9
S10
10
S11
11
S12
12
S13
13
S14
14
S15
15
S16
16
S17
17
S18
18
S19
19
S20
20
S21
21
S22
22
S23
23
S24
24
S25
25
S26
26
S39
39
S38
38
S37
37
S36
36
S35
35
S34
34
S33
33
S32
32
S31
31
S30
30
S29
29
S28
28
S27
27
KI3
52
KI2
51
KI1
50
KS6
49
KS5
48
KS4
47
KS3
46
KS2
45
KS1
44
COM
4
43
COM
3
42
COM
2
41
COM
1
40
KI4
53
KI5
54
TEST
55
VDD
56
VDD1
57
VSS
59
OSD
60
DO
61
CE
62
CL
63
DI
64
VDD2
58
U4
0
2
PT6554LQ
S3
KS5 KS4 KS3 KS2 KS1 COM
4
COM
3
COM
2
COM
1
COM
1
COM
2
COM
3
COM
4
S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S15 S16
C
401
103
TC401 47uF/
16V
DO CE CL DI
C
405
101
C4
0
4
681
R
403
4.
7K
R
404
62K
+5
V
+5
V
KI
1
R4
0
5
75R
+5
V
+5
V
GND CE CL DI DO
COM
4
20
COM
3
19
COM
2
18
COM
1
17
S16
16
S15
15
S14
14
S13
13
S12
12
S11
11
S1
1
S2
2
S3
3
S4
4
S5
5
S6
6
S7
7
S8
8
S9
9
S10
10
U
401
LCD
C4
0
3
103
C
402
103
(DNS)
(DNS)
REQUI
ER +4V TO LI
GHT
B
C E
V4
0
1
8050D
R
401
1K
LED401
R4
0
2
470R
+5
V
S17 P1/S1 S18
2 3 4 1 5 6 7
XS
401
XS0
7
IR
LED# GND IR
A K
LED402
A K
LED403
1 2
R
406
0R
R4
1
4
1K
R4
0
8
R4
0
9
V4
0
3
8550
1
2
R4
1
0
47R
SW
1
KS1 KI
2
KI
2
2 3 4 1
XS
402
XS0
4
SW
1
1 2
LED404
LED405
LED406
LED407
LED408
LED409
V
404
8050D
R
411
1K
R
412
75R
+5
V
R
413
0R
S19 S20
IN
3
GND
1
OUT
2
U4
0
4
LM
117
R4
0
7
1K
R
415
1K
TC402 47uF/
16V
TC403 47uF/
1
6V
V
402
8050D
P2/S2
P2/S2
1 2
R
416
47R
+5
V
1 2
R
418
1 2
R4
1
7
LED#
1 2
R4
1
9
4.7K
1 2
R4
2
0
4.7K
1 2
R4
2
1
4.7K
+5
V
FRONT SCHEMATIC DIAGRAM
22
9. SCHEMATIC & PCB WIRING DIAGRAM