![Kenwood KDC-348U Service Manual Download Page 31](http://html.mh-extra.com/html/kenwood/kdc-348u/kdc-348u_service-manual_188820031.webp)
31
KDC-348U/4751SD/BT41U/BT648U
/U4549/U4549SD/U549BT/X395/X695
X34-696x-xx (4/6)
23
3
3
4
6
6
6
6
6
6
6
6
17
17
20
20
20
20
21
21
21
21
21
22
22
22
22
22
22
22
23
23
23
23
23
23
24
24
24
24
21
3
3
3
3
3
25
25
25
25
25
25
25
26
26
26
27
27
28
0V
5.0V
0V
14.4V
7.1V
7.0V
7.0V
0V
14.4V
7.0V
0V
7.2V
7.0V
7.2V
7.2V
7.2V
7.0V
7.2V
0V
7.2V
7.2V
7.2V
0V
3.3V
0V
5V
0V
5V
0V
3.3V
0V
3.3V
0V
5V
0V
5V
0V
3.3V
5.1V
3.3V
0V
5.1V
3.3V
0V
0V
0V
0.25V
14.4V
4.4V
0.9V
0.7V
0V
3.3V
4.0V
8.1V
4.0V
0V
3.3V
0V
5.0V
5.0V
0V
5.0V
0V
3.3V
0V
3.3V
0V
3.3V
0V
3.3V
3.3V
0V
V
.3V
0V or 3.3V
3.3V
0V
0V
3.3V
0V
3.3V
3.3V
0V
0V
3.3V
0V
3.3V
0V
3.3V
3.3V
0V
3.3V
0V
3.3V
0V
0V
3.3V
3.3V
0V
0V
3.3V
3.3V
0V
3.3V
0V
IC801
IC802
IC71
IC51
IC21
∗
IC902
IC901
∗
Q302
Q951
POWER IC
HI SIDE SW
Q51
D51
D52
USB+5V
3.3V
to 5V
SW for IC51
FREQ CONT
SW REG
C
3.3V AVR IC
BU3.3V
∗
CN901
3.3V AVR
SD3.3V
SW
BT LPF
∗
A
BUFFER
SW3.3V SW
MODULE / SD SLOT
BLUETOOTH
∗
L
∗
M
TP903
TP904
TP909
TP905
TP902
TP910
TP907
TP900
TP908
fc = 25kHz
TP901
TP56
TP55
TP53
OUT4-
RR-
83
7
OUT2+
OFFDET
OUT2-
33K
R801
2
R821
0
C823
6
RL+
4
RL-
470P
TAB
1
STBY
5
PWRGND1
3
OUT3-
OUT4+
OUT3+
OUT1+
OUT1-
S-GND
FL
C802
C801
0.22
RL
0.22
10
8
FL+
FL-
IN1
12
14
RR
FR
C803
0.22
0.22
C804
20
IN3
16
18
FR+
22
FR-
RR+
24
IN4
SVR
VCC1
9
PWRGND2
11
C805 33u16
15
IN2
13
+
PWRGND3
AC-GND
17
19
MUTE
VCC2
21
23
84
22K
R806
R809
47K
1
R810
2.7K
C806
26
CD
R808
1K
R804
10
GND4
TAB
25
27
1
C808
TP315
VCC
3
2
1
GND
4
8
6
7
5
1K
R807
47K
R802
100
R822
82
470P
C821
470P
C824
470P
C822
470P
C828
470P
C826
470P
C827
470P
C825
100
R823
1
C807
100K
R125
R124
PWR
220u10
USB5V
C73
C52 10
OC
VOUT
R55
130K
5
4
2
1
3
VIN
GND
EN
TP52
L51
22uH
C72
0.1
105
104
22K
R71
L52
0.1
C71
5
6
7
8
GND
FREQ
VIN
BST
4
3
2
1
FB
COMP
EN
SW
0.1
C54
30K
R51
160K
R53
150P
C53
L53
160K
R52
15
R59
82K
R54
4.7
C58
62
64
1K
R57
TP54
1000P
C55
VDD
GND
CE
NC
5
4
VOUT
2
1
3
1
C23
0.01
C21
1
C22
47u6.3
C24
1
2
3 4 5 6 7
U1IN
U1OUT
VCC
VSS
SPK1P
MIC1P
SPK1N
MIC1N
∗
R913
47K
∗
R902
47K
∗
R953
66
65
MIC-P
MIC-N
51
7
5
47K
∗
R914
67
∗
R951 100
2.2
∗
C914
0.33
∗
C915
7.5
∗
R11
1000P
∗
C913
10u35
C908
0.1
∗
C909
0
R9
R956
1K
R955
0
R915
52
1
2
3
4
V+
7
8
5
6
V-
2.2
R907
10K
R908
10K
R909
10
C902
0.1
C901
100P
C903
100P
C904
47K
R904
22K
R906
0.1
C906
0.1
C905
22K
R905
47K
R903
W107
5
7
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
LX DATA S
LX DATA M
PWIC DC ERR
PWIC STBY
PWIC MUTE
MUTE AFS
MUTE 2
MUTE 1
MUTE 0
SA CLK
SA RST
PON 4V-PRE
NC
ACC DET
BU DET
ILLUMI DET
NC
NC
NC
SD CLK
BT BT DATA
BT SYS DATA
PON SW-REG
NC
FSEL1
NC
PS2-1
PS1-3
PS1-2
PS1-1
NC
NC
NC
SD CS
SD PWR
SD CD
NC
NC
DVSS
DVCC3
NC
CD MOTOR
CD DRIVE MUTE
CD CCE
CD RST
ZDET IN
CD DISC12 SW
BEEP
CD CLK
CD SI
BSIF BCK
BSIF DATA
BSIF GATE
BSIF ST REQ
MIC SW
PON PANEL3
NC
PANEL DET
NC
CD BREAK
CD LOEJ
CD PON
CD LOE LIM SW
CD SRAM STBY
CD REQ
CD LOS SW
CD SO
SD DI
SD DO
BT RST
∗
CP901 100
100
∗
R954
R234 1K
R233 100
R232 1K
R229 100
22K
R230
100
R231
100
R228
22K
R227
37
38
40
41
42
43
44
45
51
52
0.1
C210
53
53
57
58
59
60
66
65
67
72
71
47K
∗
R616
68K
∗
R620
86
85
83
84
82
81
80
79
78
77
76
73
100K
R220
100
R222
1K
R223
100
R224
100
R225
22K
R226
25
20
21
22
23
24
29
30
31
32
33
34
35
36
27
62
64
FL+B
BU
SWREG5V
1/2W
BU3.3V
BU3.3V
BU3.3V
BU3.3V
BU3.3V
SW3.3V
BU3.3V
SW3.3V
BU
SWREG5V
SWREG5V
SWREG5V
SWREG5V
SWREG5V
SW3.3V
SW3.3V
SW3.3V
SW3.3V
BU3.3V
BU3.3V
BU3.3V
BU
AM+B
BU5V
GND
OUT IN
T
S
R
Q
P