NAD M27 Service Manual - Circuit Diagram
1.MCU BOARD
12
CIRCUIT DIAGRAM
XM100
HOLE
C162 22N
R282 100R
GND
XM101
HOLE
C163 22N
R283 100R
GND
3V3S
C
13
8
22
u/
6v
3
C139
100N
GND
MCLR/VPP/RE3
1
RA0/AN0/C12IN 0-
2
RA1/AN1/C12IN 1-
3
RA2
4
RA3
5
RA4
6
RA5/HLVDIN
7
VSS
8
OSC1/CLKIN /RA7
9
OSC2/CLKOUT/RA6
10
RC0
11
RC1
12
RC2
13
RC3/SCK/SCL
14
RC4/SDI/SDA
15
RC5/SDO
16
RC6/TX/CK
17
RC7/RX/DT
18
VSS
19
VDD
20
RB0/IN T0/FLT0/AN12
21
RB1/IN T1
22
RB2/IN T2
23
RB3/AN9
24
RB4/KBI0
25
RB5/KBI1/PGM
26
RB6//KBI2/PGC
27
RB7/KBI3/PGD
28
U105
PIC18F26K20
GND
C137
NC
R216
22k
R208
10k
R210
33k
GND
VHP1
C133
100N
D119
3V6
3V3S
GND
GND
R238 100R
R220
100R
R197
100
R
PGDATA
PGCLK
MCLR
RXD
TXD
GND
3V3S
1
2
3
4
P109
Header 4
R268
100R R269
100R
C152
100n
L103
FB
GND
C147
100N
GND
RXD
TXD
MCLR
3V3S
GND
PGCLK
PGDATA
1
2
3
4
5
CON103
ICSP
R214
10K
NMOSI
q1
1
q2
2
q3
3
q4
4
q5
5
q6
6
q7
7
gnd
8
q'h
9
/sclr
10
sck
11
rck
12
/g
13
ser
14
q0
15
vcc
16
U104
74HC595
GND
C136
100N
GND
3V3D
3V3D
NCK0
R209B 100R
R209D 100R
R209C 100R
R209A 100R
R213B
100R
R213C
100R
R213D
100R
R213A
100R
3V3S
SH/LD
1
CLK
2
E
3
F
4
G
5
H
6
QH
7
G
N
D
8
QH
9
SER
10
A
11
B
12
C
13
D
1
4
CLK IN H
15
V
C
C
16
U103
HC165
R
1
9
0
A
10
k
GND
3V3D
C120
100n
GND
3V3D
C121
100N
3V3D
GND
R
1
9
0
B
10
k
R
1
9
0
C
10
k
R
1
9
0
D
10
k
NCK1
GND
R
1
8
9
A
10
k
R
1
8
9
B
10
k
R
1
8
9
C
10
k
R
1
8
9
D
10
k
q1
1
q2
2
q3
3
q4
4
q5
5
q6
6
q7
7
gnd
8
q'h
9
/sclr
10
sck
11
rck
12
/g
13
ser
14
q0
15
vcc
16
U106
74HC595
GND
C141
100N
GND
3V3D
3V3D
R230B 100R
R230D 100R
R230C 100R
R230A
100R
R237B 100R
R237C 100R
R237D 100R
R237A 100R
NCS2
GND
C140
100N
NCS1
R226
100R
R222
100R
R219
100R
R225
100R
R228
100R
R231
100R
R235
100R
NMOSI
NMIS O
NCK0
NCK1
NMIS O
NCS2
NCS1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P100 TO AMP board A
VPPi
VPNi
SCL-a
SDA-a
R126
0R
R123
0R
R128
0R
R130
0R
GPOa0
R133
0R
GND
VDR-
VDR+
+17.5V
-17.5V
R131
0R
R135
0R
AudioS
5VS
VCLIP0
b
e
c
Q105
DTC114EKA
D124
ss12
G
1
O
U
T
2
IN
3
O
4
U108
ASM1117- 3.3
C155
100n
C158
100n
5VS
3V3S
C151
22u/ 6V3
3V3S
GND
L102
742792662
C159
10n
R
24
1
10
k
R
23
9
10
K
Q135
DTC114EKA
GND
G
D
S
Q132
APM2313
5VS
5VD
C146
1N
GND
GND
5VEN
L101
742792662
G
1
O
U
T
2
IN
3
O
4
U107
ASM1117- 3.3
C
15
3
10
0n
C157
100n
3V3D
C150
22u/ 6V3
3V3D
GND
C
15
4
22
u/
6V
3
5VD
GND
R121
0R
GND
C10
1
10N
C102
10N
GND
GND
R119
0R
R120
0R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P101
TO AMP board A
VPPi
VPNi
SCL-a
SDA-a
R169
0R
R168
0R
R170
0R
R172
0R
GPOa1
R177
0R
GPOb1
GND
VDR-
VDR+
+17.5V
-17.5V
R174
0R
GPI1
R178
0R
AudioS
5VS
VCLIP1
R165
3K9
GND
C108
10N
C109
10N
GND
GND
R158
0R
R161
0R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P102
TO AMP board A
VPPi
VPNi
SCL-a
SDA-a
R193
0R
R192
0R
R194
0R
R196
0R
GPOa2
R199
0R
GPOb2
GND
VDR-
VDR+
+17.5V
-17.5V
R198
0R
GPI2
R200
0R
AudioS
5VS
VCLIP2
R188 10K
GND
C118
10N
C119
10N
GND
GND
R184
0R
R187
0R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P104
TO AMP board A
VPPi
VPNi
SCL-b
SDA-b
R218
0R
R217
0R
R221
0R
R224
0R
GPOa3
R234
0R
GPOb3
GND
VDR-
VDR+
+17.5V
-17.5V
R227
0R
GPI3
R236
0R
AudioS
5VS
VCLIP3
R215
18K
GND
C134
10N
C135
10N
GND
GND
R211
0R
R212
0R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P106
TO AMP board A
VPPi
VPNi
SCL-b
SDA-b
R252
0R
R251
0R
R253
0R
R254
0R
GPOa4
R256
0R
GPOb4
GND
VDR-
VDR+
+17.5V
-17.5V
R255
0R
GPI4
R257
0R
AudioS
5VS
VCLIP4
R248
27k
GND
C144
10N
C145
10N
GND
GND
R246
0R
R247
0R
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
P108
TO AMP board A
VPPi
VPNi
SCL-c
SDA-c
R276
0R
R275
0R
R277
0R
R278
0R
GPOa5
R280
0R
GPOb5
GND
VDR-
VDR+
+17.5V
-17.5V
R279
0R
GPI5
R281
0R
AudioS
5VS
VCLIP5
R274
47K
GND
C160
10N
C161
10N
GND
GND
R272
0R
R273
0R
1
2
3
4
5
6
7
8
9
10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
P107
T
O
A
M
P
bo
ar
d
A
VPPi
VPNi
SCL-c
SDA-c
R262
0R
R261
0R
R263
0R
R266
0R
GPOa6
R270
0R
GPOb6
GND
VDR-
VDR+
+17.5V
-17.5V
R267
0R
GPI6
R271
0R
AudioS
5VS
VCLIP6
R260
82K
GND
C149
10N
C148
10N
GND GND
R258
0R R259
0R
GPOa0
GPOb0
GPOa1
GPOb1
GPOa2
GPOb2
GPOa3
GPOb3
GPOa4
GPOb4
GPOa5
GPOb5
GPOa6
GPOb6
GPI0
GPI1
GPI2
GPI3
GPI4
GPI5
GPI6
GPI7
D112
4V7
D113
4V7
GND
GND
D114
4V7
GND
D115
4V7
D116
4V7
GND
GND
D117
4V7
GND
D120
4V7
D121
4V7
GND
GND
D122
4V7
GND
D125
4V7
D126
4V7
GND
GND
D127
4V7
GND
D131
4V7
D132
4V7
GND
GND
D133
4V7
GND
D128
4V7
D129
4V7
GND
GND
D130
4V7
GND
A
D105
4V7
D106
4V7
GND
GND
D107
4V7
GND
1
2
3
4
5
6
P105
From PSU
VDR-
VDR+
VPP
VPNi
GND
GND
PS_EN
+17.5V
-17.5V
nFATAL
OVL
nAMPON
AMPOFF
OVL
nAMPON
1
2
3
4
8
7
6
5
FB100
100M/600R
R229
100R
R232
100R
R233
100R
R223
100R
STBY
Q131
DTA114
R186
100
3V3S
R240
0R
R244
0R
SDA
SCL
R201
10k
R
20
2
0R
GND
VAUXa
C125
100N
D118
3V6
GND
3V3S
GND
R139
10
0R
C107
2N2
R141
100R
R1
44
2.
5m
R
R173
22
K
R179
22
K
D110
15V
R1
80
7K
5
GND
C115
10n
R164
47K
C114
1U
2
3
1
U102A
TL084
6
5
7
U102B
TL084
C112
470N
R152
330K
R153
330K
GND
R151
10K
R167
10K
GND
Q117
2SA1312
Q118
2SC3324
R1
60
47
K
R171
10K
R1
75
5K
1
GND
-17.5V
13
12
14
U102C
TL084
R163
6K8
R1
76
1K
GND
R136
200R
R137
200R
R138
200R
R140
200R
R159
200R
R162
200R
R166
200R
VCLIP0
VCLIP1
VCLIP2
VCLIP3
VCLIP4
VCLIP5
VCLIP6
9
10
8
U102D
TL084
R157
10K
VPNi
VPNi
VPP
GND
GND
4
11
U102E
TL084
-17.5V
+17.5V
C116
2N2
C117
2N2
GND
2
3
1
U100A
LM324
6
5
7
U100B
LM324
13
12
14
U100C
LM324
9
10
8
U100D
LM324
R101
47K
R100
1K
R112
5K6
R113
5K6
Q104
2SA1312
5VA
R122
5K1
GND
R111
100K
R1
15
15
K
R1
25
15
K
R129
100K
GND
5VS
R114
10R
C103
10U
GND
5VA
R116
100K
R1
27
10
0K
C105
10U
GND
5VA
R1
17
10
0K
GND
AudioS
5VA
4
11
U100E
LM324
GND
1
1
2
2
C104
100N
R124
100R
AudioSa
D123
4V7
C143
100N
GND
POWER_ON
A-LED
R245
100R
AUDIO SENSE
CLIPPING CONTROL
R203
0R
VHP1
DEBUG
TRIGIN
R285
47KJ
TRIGON_OFF
a1
1
gnd
2
a2
3
y2
4
vcc
5
y1
6
U109
NC7WZ17
3V3S
C164
100n
R289
120R
GND
R286
120R
R290
10R
A
M
P
M
O
D
U
L
E
1
A
M
P
M
O
D
U
L
E
2
A
M
P
M
O
D
U
L
E
3
A
M
P
M
O
D
U
L
E
4
A
M
P
M
O
D
U
L
E
5
A
M
P
M
O
D
U
L
E
6
A
M
P
M
O
D
U
L
E
7
C113
10U/35V
C156
470U/6V3
C142
220U/10V
D135
ISS352
D137
ISS352
D134
ISS352
D136
ISS352
D111
ISS352
D101
ISS352
D104
ISS352
D109
ISS352
1
2
3
4
5
6
7
8
9
10
P103
FROM regulated supply
GND
VPPi
VPNi
GND
VPPi
VPNi
GND
VPPi
VPNi
GND
VPPi
VPNi
GND
VPPi
VPNi
GND
VPPi
VPNi
GND
VPPi
VPNi
VPPi
XM102
HOLE
C166
22N
R291
100R
GND
D140
ISS352
D139
ISS352
XM103
HOLE
C167
22N
R292
100R
GND
D141
ISS352
D142
ISS352
GPI0
GPOb0
+17.5V
-17.5V
+17.5V
-17.5V
+17.5V
-17.5V
+17.5V
-17.5V
+17.5V
-17.5V
+17.5V
-17.5V
+17.5V
-17.5V
GND
GND
GND
GND
GND
GND
GND
XM104
HOLE
C168
22N
R293
100R
GND
D146
ISS352
D147
ISS352
XM105
HOLE
C169
22N
R294
100R
GND
D148
ISS352
D149
ISS352
Rt
RT1
NTC(NC)
R
18
5
10
K
+17.5V
NC
1
SCL0
2
SDA0
3
SDA1
6
SCL1
7
VCC
8
GND
4
EN
5
U110
PCA9515
NC
1
SCL0
2
SDA0
3
SDA1
6
SCL1
7
VCC
8
GND
4
EN
5
U111
PCA9515
NC
1
SCL0
2
SDA0
3
SDA1
6
SCL1
7
VCC
8
GND
4
EN
5
U112
PCA9515
C170
100N
GND
3V3D
R107
10K
R108
10K
R
10
9
10
K
R
11
0
10
K
R
30
2
10
K
R
30
3
10
K
R
30
4
10
K
R
30
5
10
K
R
30
6
10
K
R
30
7
10
K
R
30
8
10
K
3V3D
GND
SDA
SCL
SCL-a
SDA-a
C171
100N
GND
3V3D
GND
SDA
SCL
SDA-b
SCL-b
C172
100N
GND
3V3D
S
CL-c
SDA-c
GND
SDA
SCL
PWM-LED
W/R-LED
R309
10K
Q120
FMMT593TA
R326
120K
R328
4K3
1
2
3
D154
BAV99
GND
VPPi
R327
120K
R329
10K
D155
3V6
C173
100N
D158
4v7
GND
1
2
3
P112
FROM STB
GND
5VS
W
/R
-L
E
D
A
-L
E
D
1 2 3 4 5 6 7 8
CON106
5VS
GND
STB_EN
i dl i ng 0V
1
4
3
2
7
6
5
JP
10
0
1
4
3
2
7
6
5
JP101
1
4
3
2
7
6
5
JP102
VPPi
R3
25
33
K
1
2
3
4
P111
R
33
1
10
K
R
33
0
10
K
3
2
4
1
Q113
BCV62B
D159
4v7
D160
4v7
R319
1K5
P
W
M
-L
E
D
3V3D
C124
100N
C129
100N
GND
C187
NC
C188
NC
R332
6K8
R333
10K
TP1
C100
0.22u /16v
R350
47KJ
G101
PESDNC3D5VB
GND