DOWNLOAD Sharp CD-DP2500 (serv.man27) Service Manual ↓ Size: 5.13 MB | Pages: 74 in PDF or view online for FREE

Model
CD-DP2500 (serv.man27)
Pages
74
Size
5.13 MB
Type
PDF
Document
Service Manual
Brand
Device
Audio / System
File
cd-dp2500-sm27.pdf
Date
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– 49 –
CD-DP2500H
If the level is not normal, check around pins 27~29 on IC1.
1. Is focus servo activated? (Waveform drawing 49-2)
 Pins 1~11 on IC1
Check the laser diode driver Q3 peripheral circuit.
Focus error circuit (pins 20 and 21 on IC1)
When a disc is loaded, start playback operation.
2. Does DRF change from "L" to "H"?
Is the disc rotating?
3. Is the HF waveform normal?  (Waveform drawing 49-3)
Check the spin system.
If the disc is spinning and a HF waveform is generated,
DRF will go H.
Figure 49-1
Check the laser diode driver Q3 peripheral circuit.
(1) Focus-HF system check
Although a CD is inserted and the cover is closed, "NO
DISC" is displayed.
1. Did the pickup move to the PICKUP-IN Switch (SW4)
position?
Sled motor (M2)
Press the OPEN/CLOSE switch (SW1) without inserting a
disc, and try starting the playback operation.
2. Does the focus (lens) move up and down?
    (Waveform drawing 49-1).
Check the focus peripheral circuit.
3. Is the laser lit?
Spindle motor (M1).
4. Is the turntable rotating?
Figure 49-2
Figure 49-3
Yes
Yes
Yes
No
No
No
No
No
No
No
Yes
Yes
No
T
FDO
TDO
Stopped
CH1=500mV
DC   10:1
CH3=500mV
DC   10:1
500ms/div
(500ms/div)
NORM:20kS/s
1
3
=Record Length=
Smoothing :   ON
CH1  :      0.000V
CH2  :          0.0V
Main  :      100K
Zoom  :         2K
Mode  :   AUTO
Type   :   EDGE CH1
Delay  :                   0.0ns
Hold off  :                0.2us
CH3  :      0.000V
CH4  :        0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
CH1
  v/DIV
  500mV
T
FDO
DRF
TE
Stopped
CH1=500mV
DC   10:1
CH2=10V
DC   10:1
CH3=1V
DC   10:1
500ms/div
(500ms/div)
NORM:20kS/s
1
2
3
=Record Length=
Smoothing :   ON
CH1  :      0.000V
CH2  :          0.0V
Main  :      100K
Zoom  :         2K
Mode  :   AUTO
Type   :   EDGE CH1
Delay  :                   0.0ns
Hold off  :                0.2us
CH3  :        0.00V
CH4  :        0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
-3div
-1div
0div
+1div
+3div
CH  Position  To
CH2
  Position
  0.20div
Vp-p=1.0V~1.3V
0.5mV/div,0.5
µ
sec/div
CD-DP2500H
– 50 –
The tracking servo is not activated.
Check the peripheral circuits at pins 18 and 19 on IC1, pin 23 on
IC2, and CNS1A/B.
If the waveform shown in Figure 50-1 appears and soon after
NO DISC appears.
(2) Tracking system check
Check the TE waveform at pin 18 on IC1.
A normal jump operation cannot be completed or the beginning of
the track cannot be found.
Check the around pin 23 on IC2.
"Initialization" is possible, but play is not possible.
Data cannot be read. Check the VCO-PLL system.
"Initialization" is not possible.
Figure 50-1
Figure 50-2
Press the OPEN/CLOSE switch without inserting a disc, and
then try starting the play operation.
(3) Spin system check
The spin driver circuit is OK.
1. The turntable rotates a little. (Waveform drawing 50-2)
Check around pin 25 on IC2, pins 15 and 16 on IC3, and CNS3A/B.
2. The turntable doesn't rotate.
T
T
TE
DRF
Stopped
CH1=10V
DC   10:1
CH2=1V
DC   10:1
100ms/div
(100ms/div)
NORM:100kS/s
2
1
=Record Length=
Smoothing :   ON
CH1  :           0.0V
CH2  :         0.00V
Main  :      100K
Zoom  :         2K
Mode  :   NORMAL
Type   :   EDGE CH1
Delay  :               2.924ms
Hold off  :                0.2us
CH3  :         0.00V
CH4  :         0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
T
T
FDO
SPDO
Stopped
CH1=200mV
DC   10:1
CH2=500mV
DC   10:1
500ms/div
1999/04/07  09:51:15
(500ms/div)
NORM:20kS/s
2
1
=Record Length=
Smoothing :   ON
CH1  :      0.000V
CH2  :      0.000V
Main  :      100K
Zoom  :         2K
Mode  :   NORMAL
Type   :   EDGE CH2
Delay  :               2.924ms
Hold off  :                0.2us
CH3  :        0.00V
CH4  :        0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
No
Yes
No
Yes
Yes
No
– 51 –
CD-DP2500H
Is pin 35 (C2F) on IC2 "L"?
Yes
No
The HF waveform is normal and the time is displayed
normally, but no sound is produced. Or the sound
has dropouts.
(5) Others
There are too many error flags on a damaged disc which
makes error correction impossible.
Check again using a known good disc.
1. When playing at normal speed
Check the peripheral circuit at pin 37 (DOUT) on IC2 and
the waveform (Figure 51-2).
If both 1. and 2. are OK.
When a disc is loaded, start play operation.
(4) PLL system check
The HF waveform is normal, but the TOC data cannot be
read.
Check the PDO waveform. (Figure 51-1)
Check around pins 1~6 on IC2.
Figure 51-1
Figure 51-2
T
FDO
PDO2
PDO1
Stopped
CH1=500mV
DC   10:1
CH3=1V
DC   10:1
CH4=1V
DC   10:1
500ms/div
(500ms/div)
NORM:20kS/s
1
4
3
=Record Length=
Smoothing :   ON
CH1  :      0.000V
CH2  :          0.0V
Main  :      100K
Zoom  :         2K
Mode  :   AUTO
Type   :   EDGE CH2
Delay  :                    0.0ns
Hold off  :                0.2us
CH3  :        0.00V
CH4  :        0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
CH1
  v/DIV
  500mV
1999/04/05  17:33:17
T
T
DOUT
Stopped
CH1=2V
DC   10:1
500ns/div
1999/04/07  09:25:28
(500ns/div)
NORM:200MS/s
1
=Record Length=
Smoothing :   ON
CH1  :        0.00V
CH2  :        0.00V
Main  :         1K
Zoom  :      100
Mode  :   NORMAL
Type   :   EDGE CH1
Delay  :               2.887ms
Hold off  :                0.2us
CH3  :        0.00V
CH4  :        0.00V
BW   : FULL
=Trigger=
=Filter=
=Offset=
CD-DP2500H
– 52 –
FUNCTION TABLE OF IC
Figure 52 BLOCK DIAGRAM OF IC
IC1  VHiLA9235M/-1: Servo Amp. (LA9235M)
IC2  VHiLC78641E-1: Servo/Signal Control (LC78641E)
REF
LA9235M
REF
REF
REF
REF
REF
REF
REF
REF
AGCON
ODRV
AGCON
ODRV
REF
REF
LPF
LPF
APC
ODRV
REF
REF
REF
REF
LPF
PH/BH
PH
BH
1
30
FIN1
VCC
2
29
FIN2
RFSW
3
FIN3
4
27
FIN4
RF
26 N/C
25 PH
24 BH
23 N/C
5
REF1
15
16
TESI
14
TESO
13
EFBL
12
AGON
11
ODRV
10
LDOF
9
VEE
8
LDD
7
LDS
6
VREF
TES
17 HFL
18 TE
19 TE-
20 FE
21 FE-
22 RFEV
28 RF-
1
PDO1
2
PDO2
3
VVSS
4
PCKIST
5
VVDD
6
FR
7
HFL
8
SLCIST
9
SLCO
10
EFMIN
11
JITTV
12
JITTC
13
BH
14
PH(RFENV)
15
FE
16
TE
25
SPDO
26
SLDO
27
FG
28
LASER
29
CONT1
30
CONT2
CONT3
CONT4
CONT5
31
32
33
34
PCK
35
C2F
36
VDD
37
DOUT
38
FSX
39
EFLG
40
TEST
EFMO
DEFECT
FSEQ
V/P
CONT7
CONT6
VSS
VDD
DRF
RES
WRQ
INT
DO
DI
CL
CE
17
VREF
18
ADAVDD
19
ADAVSS
20
PHREF
21
BHREF
22
TBLO
23
TDO
24
FDO
SBCK
PW
SBSY
SFSY
16M
DATA
DATACK
LRSY
ASDACK
ASLRCK
ASDFIN
XVSS
XOUT
XIN
XVDD
RVDD
RCHO
RVSS
LVSS
LCHO
LVDD
MUTER
MUTEL
EMPH
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
61
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
LC78641E
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