Sony CDX-A251C Service Manual ▷ View online
29
29
CDX-A251C
CDX-A251C
3-13. PRINTED WIRING BOARDS — KEY SECTION — • Refer to page 16 for Circuit Boards Location.
: Uses unleaded solder.
1
A
B
C
D
E
F
G
H
I
J
2
3
4
5
6
7
8
9
10
11
12
13
14
1-868-120-
(21)
21
1-868-121-
(21)
21
1-868-121-
(21)
21
1-868-120-
(21)
21
AUX
6/PAUSE
SENS
4/SHUF
MODE
DSPL/DIM
SOURCE
5
CAT/BTM
PTY
BTM
LED901,S901
LCD BACK
LIGHT
LED931,932
B
MAIN BOARD
CN701
BLK
R
3
4
1
2
GND
L
BRN
BLU
R
L
2
3
1
4
5
GND
RE901
(VOLUME/PUSH DIAL SELECT)
BLU
BRN
BLK
LED951
(DISC-R)
1/GP/ALBM –
LSW918
2/GP/ALBM +
LSW917
LED952
(DISC-L)
SEEK –
. m
LED904,S904
SEEK +
M >
LED906,S906
LED902,S902
OFF
LSW913
LSW912
LED903,S903
EQ3
LED909,S909
LED941-946
(RING ILLUMINATION)
LSW915
LSW914
LED907,S907
LED908,S908
LSW911
AF/TA
(US,CND,E,MX)
(AEP,UK)
(AEP,UK)
(US,CND)
(E,MX)
SCRL
LSW910
3/REP
LSW916
SENS/BTM
(US,CND,E,MX)
(AEP,UK)
LIQUID CRYSTAL DISPLAY PANEL
56
29
1
28
LED902
S902
LED952
R955
R960
R959
R909
R963
IC971
R957
R910
R958
S901
LED932
LED931
LED901
LED951
R961
R962
S904
S903
R965
R967
R966
R968
R964
S907
S909
LED903
LED904
LED909
LED945
R993
R991
S908
S906
LED906
LED907
LED908
LED941
LED942
LED943
R997
R995
R996
R994
LED944
LED946
R971
R989
R970
R992
R990
R969
LSW918
LSW915
LSW917
LSW914
LSW916
LSW913
LSW912
LSW911
LSW910
R901
R972
C971
R979
R981
R982
D981
C981
R984
R985
R986
C983
C984
C985
D982
R931
R932
R933
R934
Q931
D903
R974
CN901
R976
IC901
R906
R907
R911
R977
R978
R987
R902
R903
R904
R915
R912
R916
R914
R913
R908
D901
R905
Q902
Q903
R953
R956
R954
R941
R942
R943
R944
R945
R946
R948
R947
R949
R952
R951
R950
R920
D902
R935
LCD901
FB901
FB902
FB903
J901
RE901
(Page 24)
( ): SIDE B
Ref. No.
Location
• Semiconductor Location
(D901)
H-11
(D902)
H-11
(D903)
H-10
(D981)
H-8
(D982)
H-8
(IC901)
H-9
IC971
D-4
LED901
A-13
LED902
A-2
LED903
D-6
LED904
B-6
LED906
B-8
LED907
D-9
LED908
C-9
LED909
C-6
Ref. No.
Location
LED931
C-13
LED932
B-13
LED941
B-8
LED942
C-8
LED943
D-8
LED944
D-7
LED945
C-6
LED946
B-7
Ref. No.
Location
LED951
A-12
LED952
A-2
(Q902)
H-6
(Q903)
H-6
(Q931)
H-13
Ref. No.
Location
30
30
CDX-A251C
CDX-A251C
3-14. SCHEMATIC DIAGRAM — KEY SECTION —
(Page 28)
R950
R948
R996
R959
R934
R906
R976
R982
R977
R979
R978
R972
R985
R945
R986
R984
R933
R989
R981
R997
R967
R964
R960
R955
R946
R971
R941
R951
R944
R947
R952
R942
R956
R968
R993
R992
R904
R914
R903
R907
R908
D901
R901
R912
R909
R931
R932
R910
R915
R902
R911
R916
R913
R920
R958
R962
R943
R949
R954
R966
R970
R991
R995
R965
R969
R990
R994
R963
R961
R957
R953
R935
RE901
LSW917(2/2)
LSW918(2/2)
LSW916(2/2)
LSW913(2/2)
LSW915(2/2)
LSW914(2/2)
LSW912(2/2)
LSW911(2/2)
LSW910(2/2)
IC971
C971
IC901
C981
C985
C984
C983
D982
R987
S901
S902
S903
S904
S907
S908
S909
LSW
910(1/2)
LSW911(1/2)
LSW912(1/2)
LSW
913(1/2)
LSW
914(1/2)
LSW
915(1/2)
LSW
916(1/2)
LSW
917(1/2)
LSW
918(1/2)
R974
S906
R905
LED902
LED901
LED952
LED951
LCD901
CN901
J901
LED904
LED909
LED903
LED946
LED943
LED941
LED944
LED942
LED945
LED906
LED908
LED907
LED931
LED932
Q931
Q903
Q902
D981
D903
FB901
FB902
FB903
D902
31
CDX-A251C
• IC Block Diagrams
IC1 BA5968FP-E2 (SERVO Board (2/2))
1
2
11
13
14
12
LEVEL
SHIFT
LEVEL
SHIFT
LEVEL
SHIFT
LEVEL
SHIFT
MUTE
FWD
FWD
LDCTL
NC
OPOUT1
NC
NC
OPOUT2
POWVCC
VCC
VOL–
VOL+
VO2–
VO2+
VO1–
VO1+
REV
OPIN4+
OPIN4–
OPOUT4
OPIN3+
OPIN3–
OPOUT3
MUTE
BIAS
GND
GND
GND
VO3–
VO3+
VO4–
VO4+
REV
OUTR OUTF
10
9
8
7
6
5
28
27
26
25
24
23
22
21
20
19
18
17
16
15
4
3
IC51 TDA7333013TR (MAIN Board (1/4))
VDDA
INTERPOLATOR
RAM
BUFFER
&
CONTROL
LOGIC
TEST LOGIC
&
PIN MUX'S
I
2
C/SPI
INTERFACE
BAND PASS
FILTER
SIGMA DELTA
CONVERTER
SINC4
FILTER
REF3
REF2
REF1
VSS
VDDD
RESETN
TM
1
MPX
16
CSN
SDAOUT
RDSREG
3
INTN
MPX
SINC4REG
SDAIN
SCK
SPI
TESTREG
SCK
SPI
TESTREG
14
2
3
4
5
6
7
8
INTN
15
SA
13
SDA
12
SCL
11
OSCILLATOR
XTO
10
XTI
9
RDS
DEMODULATOR &
SYNCHRONIZATION
2
32
CDX-A251C
IC401 BD3808AFS-E2 (MAIN Board (1/4))
32
31
30
29
28
27
26
25
24
23
22
I
2
C BUS
LOGIC
VCO
MIX
FADER
(0~-58,
-∞dB)
FADER
(0~-58,
-∞dB)
FADER
(0~-58,
-∞dB)
FADER
(0~-58,
-∞dB)
VOLUME
(+23~-79dB,-∞dB
1dB STEP)
VOLUME
(+23~-79dB,-∞dB
1dB STEP)
INPUT GAIN
(0~15dB,1dB STEP)
INPUT SELECTOR
(4 STEREO INCLUDE 1 ISOLATION INPUT)
INPUT GAIN
(0~15dB,1dB STEP)
ANTI-ALIASING
FILTER
ANTI-ALIASING
FILTER
MUTE
fc:40kHz
fc:40kHz
MUTE
6
7
8
9
10
11
3
4
5
2
1
D-GND
A-GND
FIL
AN
AUX-LCH
AUX-RCH
TU-RCH
TU-LCH
CD-RCH
CD-LCH
BUS-RCH
BUS-LCH
NC
NC
NC
NC
NC
12
14
16
13
15
SDA
SCL
MUTE
SEL
ADJ
VCC
OUT-FR
OUT-RR
OUT-FL
OUT-RL
NC
NC
NC
OUT-SUB-R
OUT-SUB-L
21
20
19
18
17
VCC
VCC/2
TONE
PASS
PASS
BASS
fo:60,70,80,100,120,140,160,200Hz
Q:0.5,0.75,1,1.25
fo:60,70,80,100,120,140,160,200Hz
Q:0.5,0.75,1,1.25
MIDDLE
fo:500Hz,1kHz
Q:1
fo:500Hz,1kHz
Q:1
TABLE
fo:5,7.5,10,12.5kHz
fo:5,7.5,10,12.5kHz
TONE
PASS
PASS
EFFECT (0dB~
+20dB,2dB STEP)
EFFECT (0dB~
+20dB,2dB STEP)
2ND ORDER
LPF
2ND ORDER LPF
fc:OFF,80,120,160Hz
Q: 0.707
fc:OFF,80,120,160Hz
Q: 0.707
BASS,TREBLE, MIDDLE
(-15dB~+15dB,1dB STEP)
BASS,TREBLE, MIDDLE
(-15dB~+15dB,1dB STEP)
GAIN+ATT
(+10~-29,
-∞dB)
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