3-13
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
PROTECTION ERROR
No display or no sound.
3-3. B(BURNT) PROTECTION
3-3-1. Solution
Replace AMP board.
3-3-2. How to troubleshoot (Countermeasure)
1)
Check PVDD voltage (23.2 V) of IC7001, IC7002, IC7003, IC7004 (easily check the pad of C7204, C7205,
C7215, C7216).
- If PVDD voltage has 8.5 V under, check SMPS.
2) Check impedance (4 Ω) of speaker unit.
- If impedance of speaker unit has 1 Ω under, replace speaker unit.
3) If check point 1), 2), 3) is OK, replace AMP board.
3-3-3. Service hint (Any picture / Remark)
PGND
C7035
1uF
50V
C7036
1uF
50V
C7037
1uF
50V
C7038
1uF
50V
C7046
33nF
C7045
33nF
C7034
33nF
C7033
33nF
C7204
330uF /35V
R7040
330K
(M)
PVDD
IC7001
26
GND_8
1
VDD
11
HEAD
35
OUT1_M
3
OTW_CLIP
8
IN1_P
6
GND_2
34
GND_10
27
OUT2_M_1
33
GND_9
7
GND_3
5
GND_1
30
PVDD_2
9
IN1_M
28
OUT2_M_2
10
RESET
29
PVDD_1
4
FAULT
31
PVDD_3
36
PVDD_4
2
GAIN/SLV
32
OUT2_P
12
OSCM
25
GND_7
13
OSCP
14
FREQ_ADJ
23
BST2_M
24
BST2_P
15
IN2_P
22
GVDD
16
IN2_M
21
AVDD
17
CMUTE
18
GND_4
19
GND_5
20
GND_6
37
PVDD_5
38
PVDD_6
39
OUT1_P_1
40
OUT1_P_2
41
GND_11
42
GND_12
43
BST1_M
44
BST1_P
FL
CEN
C7117
1uF
50V
C7118
1uF
50V
C7215
330uF /35V
C7115
1uF
50V
C7116
1uF
50V
C7126
33nF
C7114
33nF
PGND
C7113
33nF
C7125
33nF
PVDD
IC7003
26
GND_8
1
VDD
11
HEAD
35
OUT1_M
3
OTW_CLIP
8
IN1_P
6
GND_2
34
GND_10
27
OUT2_M_1
33
GND_9
7
GND_3
5
GND_1
30
PVDD_2
9
IN1_M
28
OUT2_M_2
10
RESET
29
PVDD_1
4
FAULT
31
PVDD_3
36
PVDD_4
2
GAIN/SLV
32
OUT2_P
12
OSCM
25
GND_7
13
OSCP
14
FREQ_ADJ
23
BST2_M
24
BST2_P
15
IN2_P
22
GVDD
16
IN2_M
21
AVDD
17
CMUTE
18
GND_4
19
GND_5
20
GND_6
37
PVDD_5
38
PVDD_6
39
OUT1_P_1
40
OUT1_P_2
41
GND_11
42
GND_12
43
BST1_M
44
BST1_P
TR
SR
C7043
1uF
50V
C7044
1uF
50V
C7205
330uF /35V
R7041
330K
(M)
C7041
1uF
50V
C7042
1uF
50V
C7048
33nF
C7040
33nF
PGND
C7206
330uF/35V
C7039
33nF
C7047
33nF
PVDD
IC7002
26
GND_8
1
VDD
11
HEAD
35
OUT1_M
3
OTW_CLIP
8
IN1_P
6
GND_2
34
GND_10
27
OUT2_M_1
33
GND_9
7
GND_3
5
GND_1
30
PVDD_2
9
IN1_M
28
OUT2_M_2
10
RESET
29
PVDD_1
4
FAULT
31
PVDD_3
36
PVDD_4
2
GAIN/SLV
32
OUT2_P
12
OSCM
25
GND_7
13
OSCP
14
FREQ_ADJ
23
BST2_M
24
BST2_P
15
IN2_P
22
GVDD
16
IN2_M
21
AVDD
17
CMUTE
18
GND_4
19
GND_5
20
GND_6
37
PVDD_5
38
PVDD_6
39
OUT1_P_1
40
OUT1_P_2
41
GND_11
42
GND_12
43
BST1_M
44
BST1_P
SL
TL
PGND
C7127
33nF
C7123
1uF
50V
C7119
33nF
C7124
1uF
50V
C7216
330uF /35V
C7128
33nF
C7120
33nF
C7122
1uF
50V
C7121
1uF
50V
PVDD
IC7004
26
GND_8
1
VDD
11
HEAD
35
OUT1_M
3
OTW_CLIP
8
IN1_P
6
GND_2
34
GND_10
27
OUT2_M_1
33
GND_9
7
GND_3
5
GND_1
30
PVDD_2
9
IN1_M
28
OUT2_M_2
10
RESET
29
PVDD_1
4
FAULT
31
PVDD_3
36
PVDD_4
2
GAIN/SLV
32
OUT2_P
12
OSCM
25
GND_7
13
OSCP
14
FREQ_ADJ
23
BST2_M
24
BST2_P
15
IN2_P
22
GVDD
16
IN2_M
21
AVDD
17
CMUTE
18
GND_4
19
GND_5
20
GND_6
37
PVDD_5
38
PVDD_6
39
OUT1_P_1
40
OUT1_P_2
41
GND_11
42
GND_12
43
BST1_M
44
BST1_P
FR
CT
IC7003
IC7003
C7215
C7216
C7204
C7205
IC7004
IC7001
IC7002
IC7001
IC7004
IC7002
< AMP board top view >