Sony CDX-A251C Service Manual ▷ View online
17
17
CDX-A251C
CDX-A251C
3-2. BLOCK DIAGRAM — CD SECTION —
89
RFO
RF AMP,DIGITAL SERVO,
DIGITAL SIGNAL PROCESSOR
IC2
83
RFEQO
3
RFRP
6
TEI
81 RFI
82 RFRPI
82 RFRPI
2 RFZI
7 TEZI
9 F0O
PD1
PD2
E
F
I-V AMP
PD
LD
DETECTOR
88 AGCI
94
96
95
97
100
98
TNI
FPI1
FNI1
FPI2
FNI2
TPI
91 LDO
92
MDI
(FOCUS)
(TRACKING)
2-AXIS DEVICE
OPTICAL
PICK-UP BLOCK
(KSS1000E)
• Signal Path
: CD
LASER DIODE
M
M
M
18
17
VO3–
VO3+
14
13
VO1+
VO1–
12
11 VO2–
VO2+
10
9
VOL+
VOL–
FWD
REV
1
28
OPIN4– 26
OPOUT4 25
10 TRO
OPIN3– 23
OPOUT3 22
12 FMO
OPOUT1 4
13 DMO
OPOUT2 7
MUTE 21
16
15
VO4–
VO4+
M903
(LOADING)
M901
(SPINDLE)
M902
(SLED)
FOCUS/TRACKING COIL DRIVE,
SLED/SPINDLE/LOADING
MOTOR DRIVE
IC1
51
PIO3
48
PIO0
36
MSTBY
58
ZDET
37
/RST
43
/CCE
42
BUCK
41
BUS3
CD-L
MAIN
SECTION
A
30
LO
27
RO
R-CH
27 DEC SSTBY
15 CD ZDET
15 CD ZDET
14 CD XRST
13 CD XCCE
53 MEC_SELFSW
45 MEC_INSW
42 MEC_LIMIT
12 CD BUCK
11 CD BUS3
40
BUS2
10 CD BUS2
39
BUS1
8
CD BUS1
38
BUS0
7
CD BUS0
81 X1
80 X0
MEC LOAD
43
DRVON
6
MEC EJECT
44
CD
SYSTEM CONTROL
IC3
+1.5V REG
IC6
SYSTEM CONTROL
IC501 (1/3)
37 DEC XMUTE
30 DEC INT
SW2
(SELF)
46 MEC_DSW
SW1
(DOWN)
SW3
(DISC IN)
SW4
(LIMIT)
56
UNISI
25
RXD
57
UNISO
58
UNICKI
50
BUS ON
51
BU IN
75
RSTX
61
EJECT OK
67
MECON CHK
1
CDON
1500MV
63
MECON
64
CDON
66
ZMUTE
59
LINK OFF
26
TXD
PD1
E
F
LD
MON OUT
FCS+
FCS–
TRK+
TRK–
PD2
AUTOMATIC
POWER
CONTROL
Q21
+1.5V ON/OFF
SWITCH
Q2,3
• R-ch is omitted due to same as L-ch.
24
23
X2
16.9344MHz
X1
12MHz
XI
XO
DISPLAY
SECTION
C
MAIN
SECTION
B
EJECT OK SW
UNI SI
UNI SO
LINK OFF
60
A ATT
ATT
UNI CLK
BUS ON
B/U CHECK
SYS RST
89
CD ON
VOUT
98
CDM ON
99
Z MUTE
MECHA+6V
93
68
CDON CHK
1
5
VDD
3
CE
SERVO+3.3V
+1.5V
+1.5V
BU+3.3V
(Page 18)
(Page 18)
(Page 19)
18
18
CDX-A251C
CDX-A251C
3-3. BLOCK DIAGRAM — MAIN SECTION —
1 ANT
7 TU LCH
ELECTRONIC VOLUME
IC401
J1
(ANTENNA)
TU1
(TUNER UNIT)
IC2-BUS
CONTROLLED
POWER AMP/
POWER AMP/
MULTIPLE
VOLTAGE
REGULATOR
IC750
SYSTEM CONTROL
IC501 (2/3)
CN601
6 TU RCH
R-CH (FRONT)
R-CH (REAR)
R-CH (REAR)
BATT
9 CD LCH
8 CD RCH
5 AUX LCH
3 AUX RCH
R-CH
4
3
3
10
VCC
11
TU VDD
15
E2P VDD
13
TU-SCL
14
TU-SDA
6
S-METER
7
TU MUTE
16
E2P SCL
17
E2P SDA
39 VSM
AUDIO+8.3V
TU+5V
BU+3.3V
BU+3.3V
AEP,UK
12 TU ATT
25 EEP CKO
24 EEP SIO
24 EEP SIO
8
MUTE CONDITION
5
QUALITY
RDS
53 TU ATT IN
38
38
13
QUALITY
NS MASK
DAVN
RDS ON
L-CH
R-CH
CD-L
J901
1
3
AUX
BUFFER
IC901
AUX
R-CH
11 BUS LCH
10 BUS RCH
R-CH
R-CH
17
18
18
OUT SUB-L
OUT SUB-R
R-CH
L
R
5
3
3
OUT FL+
OUT FL–
9
7
7
OUT RL+
OUT RL–
29
27
27
AMP-REM
R-CH
ANT-REM
BATT
30
37
37
AUDIO8.3V
B.UP+B
31
33
33
SERVO3.3V
MECHA6V
34
PANEL+B
TU+5V
BATT
25
24
24
OUT FR
OUT RR
29
MUTE
2 SDA
AUDIO+8.3V
+5V
SERVO+3.3V
MECHA+6V
MECHA+6V
PANEL+B
4 SCL
SDA
SCL
16 BEEP
22 STB
25 DIAG
25 DIAG
AUDIO+8.3V
35 VP
AEP,UK,E,MX
15
7
10
12
11
16
1
9
2
4
3
5
6
30
31
31
SCL
SDA
SCL
SDA
SCL
SDA
SCL
SDA
33
I2C CKO
34
I2C SIO
9
VOL ATT
86
ATT
5
BEEP
26
AMP STB
8
DIAG
54
BU IN
73
30
UNISI
58
UNISO
59
UNISCK
60
BUS ON
87
UNI SI
UNI SO
UNI CLK
BUS ON
B/U CHECK
LINK OFF
ATT
56
TEST IN
12 IN FL
FL+
FL–
RL+
RL–
FR+
FR–
RR+
RR–
BATT
AMP-REM
ANT-REM
ACC
TEST
23
OUT FL
11 IN RL
22
OUT RL
MUTE
Q441
MUTE
Q481
AUDIO OUT
REAR/SUB
J330
MUTE DRIVE
Q478,479
NS MASK
CONTROL
Q22
RDS DEMODULATOR
IC51
BATT
72
74
ACC IN
TEL ATT
ACC
CHECK
Q631
TU +5V REG
Q1
MUTE
Q461
13
ATT
D479
D511
FU601
CD
SECTION
A
CD
SECTION
B
SYS RST
DISPLAY
SECTION
D
D512
11
12
9
10
16
1
7
XTI
SCL
SCL
BU+3.3V
SDA
SDA
INTN
XTO
MPX
VDDA
VDDD
TEL ATT
CHECK
Q651
RDS B+
SWITCH
Q51
9
15
X51
8.664MHz
R-CH
L
-1
-2
-3
-4
R
BUS AUDIO IN
R-CH
BUS ON
SWITCH
Q586
LINK
SWITCH
Q587
3
1
2
3
4
6
5
7
8
BATT
6
DATA I/O
4
CLK
1
BUS ON
2
RST
BATTERY CHECK
Q580
BUS INTERFACE
IC580
D580,581
CNJ580
(BUS CONTROL IN)
RST
13
BUS IN
12
CLK IN
11
DATA IN
9
DATA OUT
8
B/U-C
10
BU+3.3V
+5V
BU +3.3V
REG
IC681
3
2
• Signal Path
• R-CH is omitted due to same as L-CH.
: CD
: FM
: AUX
: AM or MW
(Page 17)
(Page 17)
(Page 19)
19
19
CDX-A251C
CDX-A251C
3-4. BLOCK DIAGRAM — DISPLAY SECTION —
KEY ACK
ENABLE
Q664
X502
32.768kHz
79
80
82
83
41
28
29
27
40
52
76
77
SYSTEM CONTROL
IC501 (3/3)
LCD/LED DRIVER
IC901
KEYIN0
CE
LCD SO
LCD CKO
LCD CE
DIMMER
KEYIN1
31 RE-IN0
32 RE-IN1
71 RC IN1
43 RC IN0
KEY ACK
XKEY ON
3 AREASEL0
7 NOSE SW
88 SYS RST
RESET
2
1
XIN
XOUT
OSC IN
OSC OUT
X501
18.432MHz
S702
RESET
63
64
62
2
COM4
COM1
LCD901
LIQUID
CRYSTAL
DISPLAY
PANEL
D501 (1/2)
D501 (2/2)
D510
5
|
50
•
55
51
|
54
|
S1
S48
|
CL
DI
64
SIRCS
IR
LED901–904,906–909,
941–946,951,952
LSW910–918
941–946,951,952
LSW910–918
LED931,932
PANEL+B
REMOTE CONTROL
SIGNAL REVEIVER
IC971
2 OUT
BU+3.3V
SYS RST
(
)
KEY MATRIX
RESET
IC602
LSW910–918,
S901–904,906–909
(VOLUME/PUSH DIAL SELECT)
RE901
ROTARY
ENCODER
VDD VOUT
4
3
LCD BACK
LIGHT
SYS RST
CD
SECTION
C
MAIN
SECTION
D
S502
FREQUENCY
SELECT
(
)
BU+3.3V
E,MX
10K
9K
BACK LIGHT
LED CONTROL
Q931
LED DRIVER
(GREEN)
Q903
LED DRIVER
(AMBER)
Q902
•
60
J561
(REMOTE IN)
(Page 17)
(Page 18)
20
20
CDX-A251C
CDX-A251C
For schematic diagrams.
Note:
• All capacitors are in µF unless otherwise noted. (p: pF)
• All capacitors are in µF unless otherwise noted. (p: pF)
50 WV or less are not indicated except for electrolytics
and tantalums.
and tantalums.
• All resistors are in
Ω
and
1
/
4
W or less unless otherwise
specified.
•
f
: internal component.
•
C
: panel designation.
For printed wiring boards.
Note:
• X
: parts extracted from the component side.
• Y
: parts extracted from the conductor side.
•
a
: Through hole.
•
: Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
•
A
: B+ Line.
•
B
: B– Line.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
• CD mechanism (1/2) and (2/2) sections
no mark : CD
• Main (1/4), (2/4), (3/4), (4/4) and Key sections
no mark : FM
no mark : CD
• Main (1/4), (2/4), (3/4), (4/4) and Key sections
no mark : FM
(
) : AM or MW
<
> : CD PLAY
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal produc-
tion tolerances.
tion tolerances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
tion tolerances.
• Circled numbers refer to waveforms.
• Signal path.
J
: CD
F
: FM
f
: AM or MW
L
: AUX
• Abbreviation
CND : Canadian model
MX
MX
: Mexican model
Caution:
Pattern face side: Parts on the pattern face side seen from the
(Side B)
Pattern face side: Parts on the pattern face side seen from the
(Side B)
pattern face are indicated.
Parts face side: Parts on the parts face side seen from the
(Side A)
(Side A)
parts face are indicated.
Q
C
These are omitted.
E
B
E
These are omitted.
C
B
C
These are omitted.
B
E
• Waveforms
— SERVO BOARD (CD PLAY) —
— MAIN BOARD —
Note: The components identified by mark
0
or dotted line
with mark
0
are critical for safety.
Replace only with part number specified.
THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed in each block.)
(In addition to this, the necessary note is printed in each block.)
• Abbreviation
CND : Canadian model
MX
MX
: Mexican model
1
IC2
5
(FEI)
Approx.
1Vp-p
1Vp-p
0 V
0.6 Vp-p
16.9344 MHz
Approx. 100 mVp-p
50 mV/DIV, 5 msec/DIV
0.5 V/DIV, 0.5
µ
sec/DIV
2
IC2
6
(TEI)
200 mV/DIV, 5 msec/DIV
6
IC2
oh
(FPI2),
0.5 V/DIV, 0.5
µ
sec/DIV
Approx. 400 mVp-p
3
IC2
wd
(XI)
0.2 V/DIV, 0.2
µ
sec/DIV
7
IC3
ia
(X1)
0.5 V/DIV, 0.2
µ
sec/DIV
1.1 Vp-p
12 MHz
4
IC2
ia
(RFI)
0.5 V/DIV, 0.5
µ
sec/DIV
5
IC2
of
(FNI2),
og
(FNI1)
1.5 Vp-p
oj
(FPI1)
1.5 Vp-p
0 V
1 Vp-p
32.768 kHz
1
IC501
i;
(XIN)
1.3 Vp-p
18.432 MHz
2
IC501
is
(OSCIN)
1 V/DIV, 0.1
µ
sec/DIV
1.2 Vp-p
8.664 MHz
3
IC51
9
(XTI) (AEP,UK)
0.5 V/DIV, 0.1
µ
sec/DIV
0.2 V/DIV, 0.1
µ
sec/DIV
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