Sharp CD C621H Service Manual

FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER
TO THE OPERATION MANUAL.

SPECIFICATIONS

CD-C621H

General

Power source: AC 230 V, 50 Hz
Power consumption: Stand-by; 0.6 W

Power on; 89 W

Dimensions: Width; 270 mm (10-5/8")

Height; 300 mm (11-13/16")
Depth; 351 mm (13-13/16")

Weight: 6.2 kg (13.7 lbs.)

Amplifier section

Output power: PMPO; 576 W
(Except for UK) MPO; 144 W (72 W + 72 W)

(DIN 45 324)
RMS; 80 W (40 W + 40 W)
(DIN 45 324)
RMS; 66 W (33 W + 33 W)
(DIN 45 500)

Output power: RMS; 80 W (40 W + 40 W)
(For UK) (10 % T.H.D.)

RMS; 66 W (33 W + 33 W)
(0.9 % T.H.D.)

Input terminal: Video/Auxiliary (audio signal);

500 mV/47 kohms

Output terminals: Front speakers; 6 ohms

Surround Speakers; 16 ohms
Headphones; 16-50 ohms
(recommended; 32 ohms)

Compact disc player section

Type: 3-disc multi-play compact disc

player

Signal readout: Non-contact, 3-beam semi-

conductor laser pickup

D/A Converter: 1-bit D/A converter
Frequency response: 20 - 20,000 Hz
Dynamic range: 90 dB (1 kHz)

Tuner section

Frequency range: FM; 87.5 - 108 MHz

AM; 522 - 1,620 kHz

CD-C621H

Cassette deck section

Type: Compact cassette tape
Frequency response: 50 - 14,000 Hz (Normal tape)
Motor: DC motor with electronic

governor x 1

Signal/noise ratio: 55 dB (TAPE 1, playback)

50 dB (TAPE 2, recording/

playback)

Bias and erasure system: AC
Tape speed: 4.76 cm/sec. (1-7/8 ips.)
Wow and flutter: 0.2 % (DIN 45 511, playback)
(Except for UK)
Wow and flutter: 0.15 % (WRMS)
(For UK)
Heads: TAPE-1: Playback x 1

TAPE-2: Record/Playback x 1

Erase x 1

CP-C621H

Front speaker section

Type: 2-way [13 cm (5-1/4") woofer

and 5 cm (2") tweeter]

Maximum input power: 60 W
Rated input power: 30 W
Impedance: 6 ohms
Dimensions: Width; 220 mm (8-11/16")

Height; 300 mm (11-13/16")
Depth; 217 mm (8-9/16")

Weight: 2.6 kg (5.7 lbs.)/each

GBOXS0025AWM1

Surround speaker section

Type: 10 cm (4") full range speaker
Maximum input power: 20 W
Rated input power: 10 W
Impedance: 16 ohms
Dimensions: Width; 170 mm (6-3/4")

Height; 170 mm (6-3/4")
Depth; 88 mm (3-1/2")

Weight: 0.4 kg (0.9 lbs.)/each

Specifications for this model are subject to change without
prior notice.

– 3 –

CD-C621H

TROUBLESHOOTING (CD SECTION)

When the CD does not function

When the CD section does not operate When the objective lens of the optical pickup is dirty,this section may not operate.Clean
the objective lens,and check the playback operation.When this section does not operate even after the above step is taken,check
the following items.
Remove the cabinet and follow the troubleshooting instructions.
"Track skipping and/or no TOC (Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup
lens. Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned below."

Turn the power off.
Gently clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol.
Do not touch the lens with the bare hand.

Dust gradually accumulates on the objective lens during use, and it may degrade performance.
To avoid this problem, use a cleaning disc designed for CD optical pickup lenses.

HOW TO USE

1. Using the brush in the cleaner cap, apply 1 or 2 drops of the cleaning fluid to the brush on the CD cleaner disc which has
the mark next to it.

2. Place the CD cleaner disc onto the CD disc tray with the brush side down, then press the play button.

3. You will hear musicfor about 20 seconds and the CD player will automatically stop. If it continues to turn, press the stop button.

CAUTION

The CD lens cleaner should be effective for 30 - 50 operations, however if the brushes become worn out earlier then please
replace the cleaner disc.
If the CD cleaner brushes become very wet then wipe off any excess fluid with a soft cloth.
Do not drink the cleaner fluid or allow it to come in contact with the eyes. in the event of this happening then drink and / or
rinse with clean water and seek medical advice.
The CD cleaner disc must not be used on car CD player or on computer CD ROM drives.
All rights reserved. Unauthorized duplicating, broadcasting and renting product is prohibited by law.

Cleaner Liquid

Cleaning Disc
PARTS CODE:
UDSKA0004AFZZ

Figure 38

– 38 –

• When the turntable fails to stop.

5V

Is from 5 V till 2.5V down pulse (approx. 300 ms)

2.5V
0V

input into the IC701 pin 21 when the turntable is rotating?

Yes

Is there following voltage input on the IC701 pin 21 in the
specific state?
When the CD mechanism is moved up: 0V

In other states: 4.3V

Yes

Check IC2 pin26 Q91 and Q93 and the periphery.

Yes

IC701 defective.

No

No

CD-C621H

Check the SWM3 and the wiring from the IC701 pin 21 to the
SWM3.

Check the MECHA UP SW and the wiring from the IC701 pin
21 to the MECHA UP SW.

• When turntable fails to move.

Is there following voltage input on the IC701 pin 21 in the
specific state?
When the CD mechanism is moved up: 0V
In other states: 4.3V

Yes

Is L output from the IC2 pin 26 during SEC when the disc skip
switch is pressed?

Yes

Is 4V output from the Q91 emitter during operation stated
above?

Yes

Check turntable motor and turntable mechanism.

No

No

No

Check the MECHA UP SW and the wiring from the IC701 pin
21 to the MECHA UP SW.

Check the wiring of IC2 pin 26 and Q93 pin 2.

OK

IC2 defective.

Check Q91, Q93 and the periphery.

– 39 –

CD-C621H

• When the CD tray fails to open or close.

Is there following voltage input in specific state of IC701 pin 19?

Open state: 0V
Close state: 0V
Intermediate state between open state and close state: 4.3V

Yes

Is H output to IC2 pin 24 or 25 for 7 seconds when the OPEN/
CLOSE key is pressed?IC91 is defective. Replace it.

Yes

Is 4V output between IC91 pins 3 and 7 during operation
stated above?

Yes

Check the loading motor (M1) and the loading mechanism.

• The CD function will not work.

The CD operating keys don't work.

No

No

No

Check the OPEN CLOSE SW and the wiring from the IC701
pin 19 to the OPEN CLOSE SW.

Check the wiring of the IC2 pins 24 and 25, IC91 pins 1 and 3.

OK

IC2 defective.

Check the periphery of IC91.

OK

IC91 defective.

Yes

Check the CD, DSP, power supply, and 16.93 MHz clock, and
reset terminal.

Yes

Check the waveform of SCK, SO (DATA) and SI (COMM).

Yes

See if the pick-up is in the pick-up in PICKUP IN SW position.

Yes

If the items mentioned above are OK, check the main
microcomputer IC701.

• The CD operating keys work.

Check the Focus - HF system.

Playback can be performed without a disc.

Yes

Does the pick-up move up and down twice?

No

0.5s

0.50 V
IC1 16 FD

0.5s

0.50 V
IC1 7 TE

Yes

Focus search OK

Figure 40

Focus search is
performed two
times when play
operation is done
without disc.

1
2

Does the output waveform of IC1(16)(FD) match that shown in
Fig. 40?

No

Check the IC1(50)(CLK) line, 4MHz.
Check the microcomputer data on pins (51)(CL), (52)(DAT)
and (53)CE.

Yes

Check the area around IC5-CNP2.

– 40 –

• Playback can only be performed when a disc is
loaded.

CD-C621H

Is the Focus servo active? (Can you hear it working?)

Yes

Does the DRF signal change from "L" to "H"?

Yes

Is HF waveform normal (see the Fig.41-1, 2)?

Yes

Check the tracking system.

HF

1.0V/DIV

0.5µsec/DIV(DC)
(When playing
back the disc)

Figure 41-1

• Check the tracking system.

No

No

No

0.5s

1.00 V
IC1 16 FD

0.5s

10.0 V
IC2 13 CLV+

0.5s

10.0 V
IC1 54 DRF

0.5s

2.00 V
IC1 7 TE

Check the laser diode driver.
Check the area around IC1(16) - (21) (focus servo circuit).

If the disc is not turning, the DRF
should not change to "H".

Level is abnormal.

Waveform is unstable.

Yes

Yes

Yes

Figure 41-2

Check the spin system.

Check the periphery of
IC1 pins 41 and 42.

Check the spin system.

Waveform in case of
normal play-back

2
1

3
4

Check waveform of IC1 pin 7 (TE).

The waveform shown in
Fig.41-3 appears, and no­disc state appears soon.

Play is possible in
TEST mode.

Data cannot be read.

5ms

1.00 V
IC1 7 TE

5 ms

5.0 V
IC1 54 DRF

Yes

Tracking servo is

Yes

inoperative.

Although IL is possible,
play is impossible.

Yes

Check the periphery of IC 1

Yes

Yes

Check the VCO-PLL system.

pin 8 to pin 15, and IC 5 to
CNP2.

Normal jump is impeded,
and the program top
cannot be reached.

Check the periphery

Yes

of IC 1 pin 14.

4

3

Figure 41-3

– 41 –

CD-C621H

• Checking the spin system.

Play operation is performed without disc.

Yes

The turntable rotates a little.

No

The turntable fails to rotate or rotates at high speed.

• Checking the VCO-PLL system

Play operation is performed when disc exits.

Yes

Although HF waveform is normal, TOC data cannot be read.

Stop --> Play

As VCO freque­ncy is locked at

0.5s

1.00 V
IC2 3 PDO

0.5s

1.00 V
IC2 16 FD

4.32 M Hz, voltage
of PDO rises and
stabili- zes.

2

Yes

Yes

Yes

The spin driver circuit is normal.

Check the periphery of IC1 pins 23 to 27, pin 39, and pin 40, IC2
pin 12 and pin 13, IC5 to CNP3.

Check PDO waveform (Fig. 42).

Abnormal

Check the IC1 pins 43 and 44, IC2 pins 3, 5, 7, 10, and 11.

3

Figure 42

• Although HF waveform is normal and the time
indication is normal, no sound is emitted.

Check IC 2 pin 48 (EFLG).

Yes

Check IC2 pins 37, 40.

Abnomal

Check IC 401 and POWER AMP IC 801.

No

Usually, the number of pulses of flawless disc is 100 pulses/sec
or less.

– 42 –

CD-C621H

VOLTAGE

PIN
NO.

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
37
38
39
40
41
42
43
44
45
46
47
48
49
50

51
52
53
54
55
56
57
58
59
60
61
62
63
64

1
2
3
4
5
6
7
8
9

IC1

VOLTAGE

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V
0V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.5V

2.3V

2.3V
0V
0V

5.0V

5.0V
0V
0V

5.0V
0V
0V

1.6V

2.4V

2.4V

2.4V
0V

2.5V

2.5V
0V
0V

2.4V

4.6V

4.6V
0V
0V

5.0V

5.0V

2.5V

2.5V

1.0V

1.0V

2.2V

4.2V
0V

5.0V

PIN
NO.

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
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64

1
2
3
4
5
6
7
8
9

IC2

VOLTAGE

0V
0V
0V
0V

1.9V

5.0V
0V
0V

2.5V

2.4V
0V
0V
0V

5.0V
0V
0V

5.0V

5.0V
0V
0V

2.5V
0V

5.0V
0V
0V
0V
0V
0V
0V

5.0V

2.5V
0V
0V
0V

5.0V

4.6V

1.9V
0V
0V

1.9V

4.6V

5.0V

5.0V

2.1V

2.1V
0V

0.1V

2.3V
0V

2.5V
0V

2.5V
0V
0V
0V

4.6V

4.6V

4.7V
0V

2.3V

2.3V
0V
0V
0V

PIN
NO.

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
37
38
39
40
41
42

PIN
NO.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

1
2
3
4
5
6
7
8
9

1
2
3
4
5
6
7
8
9

IC3

VOLTAGE

2.5V

2.6V

2.9V

3.3V

3.3V

3.3V

3.3V
0V
0V
0V
0V
0V
0V
0V

3.3V

3.3V

3.0V

7.2V

5.0V

2.5V
0V
0V
0V

7.2V

2.5V

3.3V

3.3V

11.2V
0V
0V
0V
0V
0V
0V
0V

5.3V

5.3V

3.3V

3.3V

7.2V

0.1V

0.1V

IC101

VOLTAGE

0V (0V)
0V (0V)

0.5V (0.5V)

4.3V (4.3V)

0.2V (0.3V)

1.3V (1.3V)
0V (0V)

0.6V (0.6V)

4.1V (4.1V)

4.0V (4.0V)
0V (0V)
0V (0V)

8.1V (8.1V)

4.8V (4.8V)
0V (0V)

4.1V (4.1V)

0.6V (0.6V)
0V (0V)

2.5V (2.6V)

0.2V (0.3V)

4.3V (4.3V)

0.5V (0.5V)
0V (0V)
0V (0V)

PIN
NO.

1
2
3
4
5
6
7
8

PIN
NO.

1
2
3
4
5
6
7
8

PIN
NO.

1
2
3
4
5
6
7
8

PIN
NO.

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

FE301

VOLTAGE

0V (0V)
0V (0V)

2.6V (0V)
2V (1.1V)

8.5V (0V)
0V (0V)
0V (0V)
0V (0V)

IC562

VOLTAGE

0.12V

0.1V

0.13V
–11.2V

0.1V

0.1V

0.1V

6.2V

IC563

VOLTAGE

0.2V

0.2V

0.2V
–9.8V

0.2V

0.2V

0.2V

6.2V

ICT21

VOLTAGE

2.6V(0.3V)

2.6V(0V)

5.1V(0V)
0V(0V)

2.6V(0V)

2.6V(0.2V)
0V(0V)
0V(0V)
0V(0.3V)

0.1V(0.3V)

0.1V(0.3V)

2.6V(0V)

2.5V(0V)

5.1V(0V)
0V(0V)
0V(0.4V)
0V(0.3V)

0.2V(0.3V)

0.2V(0.4V)

0.1V(4.5V)

4.1V(4.1V)
0V(0V)

0.5V(0.5V)
0V(0V)

PIN
NO.

10
11
12
13
14
15
16
17
18
19
20
21
22

PIN
NO.

10
11
12
13
14
15
16
17
18
19
20

PIN
NO.

1
2
3
4
5
6
7
8
9

1
2
3
4
5
6
7
8
9

1
2
3

IC302

VOLTAGE

2.6V (2.6V)
0V (0V)
0V (0.5V)
0V (0V)

4.1V (4.1V)

4.7V (4.7V)

0.2V (11.8V)

0.5V (0.1V)

0.2V (0.2V)
0V (0V)

5.1V (5.1V)

2.5V (2.5V)

5.1V (5.1V)
0V (0V)
0V (2.5V)

2.5V (0V)

5.1V (5.1V)

0.9V (0.9V)

0.9V (0.9V)

1.9V (1.1V)
0V (0V)

2.5V (2.5V)

IC601

VOLTAGE

0V
0V
0V
0V
0V
0V
0V
0V
0V

2.7V

0.2V
–2.7V
0V
0V
0V
0V
0V
0V
0V
0V

IC704

VOLTAGE

5.0V
0V

5.0V

PIN
NO.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

PIN
NO.

10
11
12
13
14
15

PIN
NO.

10
11
12
13
14
15
16
17
18

1
2
3
4
5
6
7
8
9

1
2
3
4
5
6
7
8
9

1
2
3
4
5
6
7
8
9

IC303

VOLTAGE

2V (2V)
5V (5V)
2V (2V)
0V (0V)
5V (5V)
5V (5V)

5.1V (5.1V)

2.9V (3.5V)

5.1V (5.1V)

0.1V (0.1V)

3.9V (1.2V)

3.9V (1.2V)

2.2V (2.2V)

1.1V (1.1V)

1.1V (1.1V)
2V (2V)

0.2V (0.1V)

2.0V (0.8V)
0V (1.8V)

0.4V (0.8V)

2.6V (2V)

2.6V (2V)

5.1V (5.1V)

3.6V (3.6V)

IC901

VOLTAGE

–30.4V
–30.4V

30.5V
0V
0V
0V
0V
–29.4V

29.4V
–0.1V
–0.1V
–28.0V
–0.1V

0.1V
0V

IC703

VOLTAGE

0V
0V
0V
0V

0.8V

0.8V

0.9V

0.9V

0.8V

0.8V

0.7V
0V
0V
0V

9.8V

9.8V
0V

5.0V

PIN

VOLTAGE

NO. NO.

4.8V

1

4.8V

2

4.8V

3

0V

4

0V

5

0V

6

0V

7

0V

8

0V

9

4.0V

10

2.3V

11

2.3V

12

0V

13

4.9V

14

0V

15

4.9V

16

0V

17

4.8V

18

0V

19

4.8V

20

4.8V

21

0V

22

0V

23

0V

24

0V

25

0V

26

0V

27

0V

28

0V

29

0V

30

5.0V

31

5.0V

32

5.0V

33

4.8V

34

5.0V

35

4.7V

36

5.0V

37

4.8V

38

4.9V

39

0V

40

4.7V

41

0V

42

3.6V

43

11.3V

44

11.3V

45

4.8V

46

4.7V

47

4.7V

48

4.7V

49

0V

50

PIN

51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99

100

Q821

IC701

PIN
NO.

1
2
3

VOLTAGE

11.3V

6.2V

1.2V

PIN
NO.

Q823

PIN
NO.

1
2
3

VOLTAGE

12V

19.6V

11.3V

PIN
NO.

VOLTAGE

Q822

VOLTAGE

1
2
3

Q824

VOLTAGE

1
2
3

4.8V

4.8V
0V

4.8V
0V
0V
0V

4.7V

4.8V

4.7V
0V

4.8V

5.0V

5.0V

5.0V
–28V
–28V
–28V
–28V
–28V
–28V
–28V
–28V
–20V
–28V
–22.6V
–25.4V
–22.6V
–27.8V
–25.4V
–25.3V
–25.3V
–22.5V
–25.3V
–22.7V
–27.3V
–22.7V
–17.4V
–20V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V
–25.4V

19.6V

1.3V

7.3V

19.6V
0V

12.0V

– 36 –

1

PLAY

TCD-712

5s
100mV
SLD

1

2

5ms

0.50 V
IC1 20 F.E

5ms

5.0 V
IC1 54 DRF

WAVEFORMS OF CD CIRCUIT

STOP PLAY

FOCUS SERCH

0.5ms

6

10.0 V
JP+

0.5ms

7

10.0 V
JP-

0.5ms

8

0.50 V

3
1

JP

0.5ms

9

1.00 V
TE

CD-C621H

0.5ms

3

1.00 V
HF

0.5ms

4

5.0 V
HFL

0.5ms

5

5.0 V
TES

0.5ms

1.00 V

3

HF

0.5ms

4

5.0 V
HFL

0.5ms

5

5.0 V
TES

50ms

6

10.0 V
JP+

50ms

7

10.0 V
JP-

50ms

8

0.50 V
JP

50ms

9

1.00 V
TE

CUE

1
2

3

REVIEW

1
2

3

CUE

10

11

10

11

12

20ms

1.00 V
SPO

20ms

2.00 V
CLV+

50ms

1.00 V
SPO

50ms

2.00 V
CLV+

PLAY

NORMAL DISC
TN0=01

PLAY

TCD-712 (140mm)
TN0=01

0.5ms

10.0 V

6

JP+

0.5ms

10.0 V

7

JP-

0.5ms

0.50 V

8

JP

0.5ms

9

1.00 V
TE

50ms

10.0 V

6

JP+
50ms

10.0 V

7

JP­50ms

8

0.50 V
JP

50ms

9

1.00 V
TE

REVIEW

12

0.5s
100mV
SLD

1

– 37 –