Cambridge Audio 640A - Front Panel Circuit Schematics; Front Panel Circuit Diagram

Cambridge Azur 640A Integrated Amplifier
AP12711/9 Front Panel Schematics
temp
dc
clip
speaker relay
overcurrent/short
standby relay
REMOTE IN
RB7
17
RB6
16
RB5
15
RB4
14
RB3
13
RB2
12
RB1
11
RB0
10
VDD
2
VSS
4
RTCC
1
N/C
3
N/C
5
RC4
22
MCLR/VPP
28
RA0
6
RA1
7
RA2
8
RA3
9
RC5
23
RC6
24
CKIN
27
RC7
25
CKOUT
26
RC1
19
RC0
18
RC2
20
RC3
21
U5
PIC16C57
CRS1
FREQ=4MHz
1
2
CN7
H2 2.54mm 90
MOTOR
D1
1N4148
C21
100n
FIN
1
GND1
2
RIN
3
NC
4
GND2
5
VCC
6
OUT2
7
COM
8
OUT1
9
U6
BA6218
C22
100n
+5V
DGND
DGND1
R27
10k
R28
10k
R29
10k
+5V
DGND1
+5V
DGND1
+5V
DGND1
C23
100n
R30
33k
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
VDD
16
VSS
8
U7
74HC4094
R33
820R
+5V
C24
100n
D2
CHANNEL LED
D3
CHANNEL LED
D4
CHANNEL LED
D5
CHANNEL LED
D6
CHANNEL LED
D7
CHANNEL LED
SW3
STANDBY
SW4
CD
SW5
TUNER
SW6
AV
SW7
PHONO/AUX
SW9
TAPE MON
SW10
DVD
D8
Red LED
protection
lead mounted
+5V
3
OPT
1
GND
2
U9
TSOP18 IR RECEI
R35
10k
+5V
HEADPHONE
HEADPHONE
C1
100n
+5V
DGND
R1
220R
strobe
data
clock
clock
data
strobe
vol up
vol down
vol up
vol down
R2
10k
C3
47u 16V
LK1
LINK
DGND1
R3
820R
LK5
LINK
LK3
LINK
C4
100n
1
2
3
4
5
6
7
8
CN2
H8 2.54mm 90
DGND
+5V
1
2
3
4
CN1
H4 2.54mm 90
LK8
LINK
LK9
LINK
R4
10k
D9
Blue flat top LED
Standby
DGND1
1
2
3
4
5
6
7
8
9
CN6
H9 2.54mm 90
1
2
3
4
5
6
7
8
9
CN5
CONN-H9
DGND1
Q2
BC337
R5
10k
R6
820R
DGND1
R7
820R
SNAP OFF SECTION (c)
SNAP OFF SECTION (d)
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