NAD C521 User manual
NAD
Schematics
C 521
COMPACT
DISC PLAYER
C 521
COMPACT
DISC PLAYER
CATUION
HGKJDHSGKJHGSJK
ADVARSEL
HGKJDHSGKJHGS
KBVNCLKNBCVLKNLKNVLKNCVNCLVK JK
ADVARSEL
HGKLFH;L;HJMNMD
HFKLJHJLDKLJLKDJLKFHJHSGMMKJHGSJK
VARING
HGKJDHSGKJHGKLGDJH
KLHKFG;LKNG;LKJGF;LKJGF;LKJFL;SJK
VARO!
HGKJDHSGKJHJBJKBKJBJKGS
KBVNCLKNBCVLKNLKNVLKNCVNCLVK JK
VORSICT!
HGKLFH;L;HHBHHJD
JHFKLJHJLDKLJLKDJLKFHJHSGKJHGSJK
2
SAFETY INFORMATION
CAUTION
CAUTION
- INVISIBLE LASER RADIATION WHEN OPEN AND
INTERLOCKS DEFEATED.AVOID EXPOSURE TO BEAM.
ADVARSEL
- USYNLIG LASERSTRÅLING NÅR DEKSEL ÅPNES OG
SIKKERHEDSLÅS BRYTES. UNNGÅ EKSPONERING FOR STRÅLEN.
ADVARSEL
- USYNLIG LASERSTRÅLING VED ÅBNING, NÅR
SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGÅ
UDSÆTTELSE FOR STRÅLING.
VARING
- OSYNLING LASERSTRÅLNING NÄR DENNA DEL ÄR
ÖPPNAD OCH SPÄRRAR ÄR URKOPPLADE. STRÅLEN ÄR FARLIG.
VARO!
-AVATTAESSAJASUOJALUKITUS OHITETTAESSA OLET
ALTTIINANÄKTMÄTÖNTÄ LASERSÄTEILYLLE. ÄLÄ KAISO
SÄTEESEEN.
VORSICT!
- UNSICHTBARE LASERSTRAHLUNG TRITTAUS, WENN
DECKEL GEÖFFNET UND WENN SICHERHEITSVERRIEGELUNG
ÜBERBRÜCKT IST. NICHT DEM STRAHLAUSSETZEN.
THIS DEVICE COMPLIES WITH PART 15 OF THE FCC RULES.
OPERATION IS SUBJECT TO THE FOLLOWING TWO CONDITIONS:-
(1) THIS DEVICE MAY NOT CAUSE HARMFUL INTERFERENCE, AND
(2) THIS DEVICE MUST ACCEPT ANY INTERFERENCE RECEIVED,
INCLUDING INTERFERENCE THAT MAY CAUSE UNDESIRED
OPERATION.
The lightning flash with arrowhead, within an equilateral tri-
angle is intended to alert the user of the presence of
uninsulated "dangerous voltage" within the product’s
enclosure; that may be of sufficient magnitude to consti-
tute a risk of electric shock to persons.
The exclamation point within an equilateral triangle is intend-
ed to alert the user of the presence of important operating
and maintenance (servicing) instructions in the literature
accompanying the appliance.
CLASS 1
LASER PRODUCT
3
SERVICE SAFETY PRECAUTIONS
1. Replacing the fuses
CAUTION: FOR CONTINUED PROTECTION AGAINST THE RISK OF FIRE REPLACE ONLY
WITH SAME TYPE OF FUSE.
Reference No Part Number Description
M502-M504 *AH 5120-0020-0 FU T1A 250V UL/CSA 5X20MM
M502-M504 *C 5120-0018-0 FU T1A 250V SEMKO/UDE 5X20MM
M505 *AH 5120-0052-0 FUSE T1.6A 250V 5X20MM UL/CSA
M505 *C 5120-0050-0 FUSE T1.6A/250V 5X20MM SEMKO/VDE
NOTE:
<*AH > : USA, CANADIAN MODEL ONLY.
<*C > : EUROPEAN MODEL ONLY.
2. Safety check out
(Only U.S.A. model)
Before returning the product to the customer, make leakage current or resistance measurements
to determine that exposed parts are acceptably insulated from the supply circuit.
Parts marked with the symbol are critical with regard to the risk of fire and electric shock.
Replace only with parts recommended by the manufacturer.
CONTENTS
DESCRIPTION PAGE
SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
REAR PANEL / FRONT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
DISASSEMBLY INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
RF PATTERN TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
IMPORTANT NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10-11
PCB LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-14
SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-16
IC BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-20
TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
ELECTRICAL PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-26
MECHANISM EXPLODED VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
MECHANISM EXPLODED VIEW PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
EXPLODED VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
EXPLODED VIEW PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
PACKING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
4
SPECIFICATIONS
Disc Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . One Disc, 120 or 80 mm
Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BURR-BROWN Delta Sigma 20bit
Digital Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Times oversample
Analog Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 pole active
Frequency Response . . . . . . . . . . . . . . . . . . . . . . +/- 0.5 dB, 5Hz - 20kHz
De-Emphasis Error . . . . . . . . . . . . . . . . . . . . . . . . +/- 0.3 dB
THD (at 0 dB, 1kHz) . . . . . . . . . . . . . . . . . . . . . . . 0.007%
Intermodulation Distortion . . . . . . . . . . . . . . . . . . . < - 100 dB
(19 + 20 kHz)
Dynamic Range . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 dB
Linearity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +/- 0.5 dB, 0 dB to -80 dB
Signal / Noise Ratio (A-Weight) . . . . . . . . . . . . . . . 100 dB, De-Emphasis on
100 dB, De-Emphasis off
Channel Separation 1kHz . . . . . . . . . . . . . . . . . . >90 dB
10 kHz . . . . . . . . . . . . . . . . . >80 dB
Wow and Flutter . . . . . . . . . . . . . . . . . . . . . . . . . . Unmeasurable (Quartz Crystal Accuracy)
Output Impedance . . . . . . . . . . . . . . . . . . . . . . . . . 200
Output Level at 0 dB . . . . . . . . . . . . . . . . . . . . . . . 2.2 V rms
Digital Error Correction . . . . . . . . . . . . . . . . . . . . . IRC with double error correction
in C1 and C2
Digital Code Output . . . . . . . . . . . . . . . . . . . . . . . . Sony / Philips Serial data format
CONTROLS
Play / Pause, Stop, Random, Skip (< >), Scan (< >), Open, Time, Repeat.
PHYSICAL SPECIFICATIONS
Dimensions 435 x 80 x 285 mm
(Width x Height x Depth)
Net weight 4 kg (8.8 lbs)
Shipping weight 5.1 kg (11.22 lbs)
5
REAR PANEL / FRONT PANEL
REAR PANEL
FRONT PANEL
1. LINE OUT
2. DIGITAL OUT 3. AC LINE CORD
1. POWER ON / OFF
2. DISC DRAWER
3. DISPLAY
4. OPEN
5. PLAY / PAUSE
6. TIME
7. STOP
8. REPEAT
9. RANDOM
10. SCAN Back ( ) / Forward ( )
11. SKIP Back ( ) / Forward ( )
6
DISASSEMBLY INSTRUCTIONS
1. Remove machine screws M 4.0 x 6.0 ( 1 to 4 ) from the side panels.
Remove tapping screw 3.0 x 8.5 5 from the back panel.
Refer to Figure No.1.
Figure No.1
2. Pull both sides of the TOP COVER slightly outwards 6 and tilt approx. 35˚ and then remove
in the direction as indicated by the arrow 7 . Refer to Figure No.2.
Figure No.2.
5
4
3
1
2
7
6
6
7
BLOCK DIAGRAM
U401 LC587206A
SYSTEM CONTROL CPU
& LCD DISPLAY DRIVER
Q401- Q403
MUTE CIRCUIT Q301-Q304
MUTE
M317
RCA
JACK
U302
PMC1710
M318
RCA JACK
DIGITAL
OUTPUT
M501*
LCD DISPLAY
3
56 19
2
63
23 29 39 62
37
1
2
16
13
3
42
44
43
23
24
14
13
33
34
31
32
21
22
65
67
2 4
3 6
56
L
R
L
R
CD AUDIO
O/P
10 11
30 31
5 6
35
34
39
40
4443
1
63 62
U301
LC78621
DIGITAL
SIGNAL
PROCESSOR
15
27
16
29
2 10
5
10
6
11
20
25
21
26
3
18
13
28
U101 LA9240
ANALOG SIGNAL
PROCESSOR/SERVO
TOFF
TGL
CLV-
CLV+
EFM
U701 LB1641
MOTOR DRIVER
U201 LA6541
FOCUS &
TRACKING
MOTOR
DRIVER
LOADING
MOTOR
LOADING MOTOR
LIMIT SWITCH
SPINDLE
MOTOR
SLED
MOTOR
PU-IN
LIMIT SWITCH
PICK
UP
DISC
KEYBOARD
M113
REMOTE
SENSOR
CD MECHANISM UNIT
POWER
TRANSFORMER
AC POWER I / P
M110 M109
REPEAT
M104 M111M112
RANDOM
M106
M101 M103 M102
TIME
M108
Q101
DAC
U306 U305
4
U501,U507
DIGITAL
POWER
U502-3,U506
ANALOGUE
POWER
+8V +5V +12V 5V
-12V
D514-D517
RECTIFIER
DIODES
D501-D504
RECTIFIER
DIODES
D506
RECTIFIER
DIODES
U504
POWER FOR
EL LIGHT
M502
EL LIGHT
U403
74HC00
NAND GATE
M303
EMC FILTER
L301
DIGITAL COIL
T1
1
8
WIRING DIAGRAM
M102
(15 PINS)
M505B WHITE
M505A WHITE
M509A
BLACK
M120 BLACK
M500A
BLACK
M805
BROWN
NEUTRAL
LIVE
M803
BROWN
J402
M105 (6 PINS)
M101 (5 PINS)
MAIN BOARD
TRANSFORMER BOARD
DISPLAY
BOARD
LIVE BOARD
CD MECHANISM
KEYBOARD
115V:J401,J404
230V:J403
L401
J403
J406
J407
J402
J404
J401
1723-006A-0000
8V
0V
0V
8V
15V
0V
15V
ISSUE B
9
RF PATTERN TESTING
NAD - C 521 PCB TESTING POINTS DIAGRAM
TESTING PROCEDURE
(1) Load the test disc (Sony Test CD YEDS-7) and set the unit into PLAY mode.
(2) Connect the scope to R132 (Pin 41 of U101) and DGND (J334).
Scope setting: Coupling : AC.
Vertical sensitivity : 0.2 V/ div.
Horizontal time base : 0.5 µS/div.
(3) Observe the waveform is 2.0V p-p +/-5% and the eye pattern is at its best shape (see FIG. 1).
FIG. 1 (a) FIG. 1 (b) Poor eye pattern
FIG. 1 (C) Good eye pattern
3T 4T 5T — 11T
10
IMPORTANT NOTES
INSTRUCTION FOR HANDLING OPTICAL SYSTEM BLOCK PICK-UP
Electrostatic breakdown of the laser diode in the optical system block may occur due to a poten-
tial difference caused by electrostatic charge accumulated on clothing, human body, etc. A ground
must be provided as follows to prevent any electrostatic charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a ground band (1M ohm) that is properly to remove any static electricity that may
be charged on the body.
2. Ground for Work Bench
Be sure to place a conductive sheet (1M ohm) or copper plate with proper grounding on the work
bench or other surface on which the pick-up is to be placed.
3. Because the static electricity charge on the clothing does not discharge through the body
grounding band, do not let clothing to get in contact with the pick-up unit.
PRECAUTIONS FOR CHECKING BEAM EMISSION
The laser beam of this unit is focused on the reflecting surface of the objective lens in the optical
system block. Therefore, keep your eyes at least 12 inches (30 cm) away from the objective lens
when the laser diode is ON.
(Operation Check Method for Laser Diode and Focus Search Function.)
When the POWER switch is turned ON after the chucking plate is removed, observe the objective
lens and confirm that the following operations are performed properly.
(The optical system should be at the lead-in area position when it is checked at this time.)
(1) The laser should be at the innermost position after the chucking plate is removed.
(2) The diffused light of the laser beam can be seen when the POWER switch is turned ON.
(3) Vertical (up and down) movement of the objective lens (2 or 3 times) will take place.
INCORRECT CORRECT
NOTE: Laser diodes are so susceptible to damage from
static electricity that even if a static discharge does not
ruin the diode, it can shorten its life or cause it to work
improperly.
1.Grounding band
1M ohm
1M ohm
2.Conductive Sheet
or Copper Plate
11
PRECAUTIONS WHEN CHANGING LASER PICK-UP
When removing the pick-up assembly, short circuit the PCB tracks on the optical block as show in
the drawing in order to protect the pick-up before removal.
NOTE: Replacement pick-up assemblies are supplied with the PCB pattern already protected.
DO NOT REMOVE THE SHORT CIRCUITS UNTIL YOU HAVE FINISHED FITTING THE PICK-
UP.
Caution:
Laser diodes are extremely susceptible to damage from static electricity. Even if a static dis-
charge does not ruin the diode, it can shorten its life or cause it to work improperly. When replac-
ing the pick-up, use a conductive mat, a grounded soldering iron, and so on, to protect the laser
diode from static damage. Ground Conductive
Wrist Band for Body
Ground Line
Less than
10 ohm
Conductive Gum Mat
Soldering
Iron with
Ground
wire
Protective soldering place
for laser diode
12
PCB LAYOUT
TRANSFORMER BOARD
LIVE BOARD
KEY BOARD
DISPLAY BOARD
115V:J401,J404
230V:J403
L401
J403
J406
J407
J402
J404
J401
1723-006A-0000
8V
0V
0V
8V
15V
0V
15V
ISSUE B
1413
MAIN BOARD
15 16
SCHEMATIC DIAGRAM
M502
M501
5V
0V
4.3V
2.2V
5V
0V
0V
0V
0V
0V
2.4V
1.6V
0V
0V
0V
4.9V
0V
0V
4.8V *0V
4.8V *1.2V
4.9V *0V
5V
5V
2.4V
0V
1.1V *2.7V
1.2V *2.7V
*7.4V
7.8V
2.5V
2.5V
2.5V
3.4V
3.4V
0V
0V
0V
3.5V
3.5V
2.5V
2.5V
4.8V
4.9V
*7.4V
7.8V
*5V 0V
2.4V
2.5V
*3.3V
3.5V
*2.9V
3.5V
0V
0V
0V
3.4V
3.4V
2.5V
2.5V
5V
*7.4V
7.8V
0V
0V
0V
5V
5V
5V
5V
4.9V
4.9V
4.9V
4.9V
0V
4.8V
2.6V
2.4V
¨4.9V
#0V
#4.9V
¨0V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2V
3.7V
0V
0V
0V
0V
0V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
2.4V
5V
0V
3.3V
1.6V
0V
4.7V
4.8V
0V
0V
0V
0V *1.8V
5V
5V
0V
4.9V
4.9V
0V
5V
2.3V
2.2V
0V
0V
2.4V
2.3V
4.9V
4.9V
4.9V
0V
0V
*1.4V 4.6V
0V
1.7V
5V
1.5V
*0.3V 0V
2.3V
2.5V
2.5V
0V
*0.4V 0V
0V
0V
0V
0V
0V
0V
4.9V
4.9V
0V 0V
0V 0V 0V 0V 0V 0V 0V 0V 0V 0V 0V
0V
2.4V
2.4V
3V *1.6V
0V *1.8V
0V
2.4V 2.4V
5V
2.3V
0.2V
*0V 4.9V
0V
0.7V
0.5V
0V
0V
7.8V
7.8V
0.7V
0.5V
¨0.06V #4.2V
*1.2V 3V
2.4V
2.4V
2.1V
2.3V
2.3V
0V
0V
2.4V
2.5V
0V
5V
5V
0V
5V
0V
4.9V
0V
2.3V
0V
0V
2.4V
2.5V
5V
5V
5V
NOTE: 1. RESISTORS, UNLESS OTHERWISE SPECIFIED, ARE 1/8W.
2. ALL CERAMIC CAPACITORS, UNLESS OTHERWISE SPECIFIED, ARE
50V 10%.
3. COMPONENTS MARKED “ ” ARE SAFETY CRITICAL PARTS.
4. VOLTAGE SPECIFIED ON THE IC’S PIN WHICH DOES NOT HAS
MARKING IS IN STOP MODE, MARKED WITH “*” IS PLAY MODE, “#” IS
TRAY OPEN MODE AND “Δ“ IS TRAY CLOSE MODE.
RESISTORS: M- METAL FILM
CARBON FILM UNLESS OTHERWISE SPECIFIED.
64
VCC1
63
LDS
62
LDD
61
BH1
60
PH1
59
LF2
58
VR
57
REFI
56
VCC2
55
FSS
54
DRF
53
CE
52
DAT
51
CL
50
CLK
49
DEF
48 NC
47 TBC
46 FSC
45 DGND
44 SLI
43 SLC
42 RFS–
41 RFSM
40 CV+
39 CV–
38 SLOF
37 HFL
36 TES
35 TOFF
34 TGL
33 JP+
32
JP–
31
SL+
30
SL–
29
SLD
28
SLEQ
27
SPD
26
SP–
25
SPG
24
SPI
23
SP
22
AGND
21
FE–
20
FE
19
FA–
18
FA
17
FD–
1
FIN2
2
FIN1
3
E
4
F
5
TB
6
TE–
7
TE
8
TESI
9
SCI
10
TH
11
TA
12
TD–
13
TD
14
JP
15
TO
16
FD
REF
BAL
I/V
TE
T.SERVO & T.LOGIC
F.SERVO & F.LOGIC SPINDLE SERVO
SLC
APC
RF DET
VCA
RF Amp
- com
INTER FACE
VCA
SLED SERVO
EFMO
DEFI
EFMIN
LRSY
C2F
ROMXA
DOUT
ASDACK
ASDFIN
ASDFIR
ASLRCK
DACKO
DFOLO
DFORO
LRCKO
FSEQ
CLV+
CLV–
V/P
PW,SBCK
SBSY,SFSY
WRQ,SQOUT
CQCK
COIN
RWC
DEMO
FST,FOCS
FZD
HFL,RES
TES,JP+
TOFF,JP–
THLD,TGL
EMPH
LASER
16M
4.2M
CS
CONT
EFLG
FSX
XIN
XOUT
XVDD,XVSS
CK2
RVDD,RVSS
MUTER
RCHP
RCHN
LVDD,LVSS
LCHN
LCHP
TGL
EFMO
VVDD
VVSS
PDO
ISET
PCK
TAI
TST11
TST10
TSET1
TEST2
TEST3
TEST4
TEST5
VDD
VSS
2K x 8-bit RAM RAM address
generator
Interpolation
and muting
Antishock
interface
Digital
attenuator
8x oversampling
digital filters
Level meter
Peak meter
Crystal oscillator system
Timing generation
C1 AND C2 ERROR DETECTION
AND CORRECTION
FLAG PROCESSING
CLV DIGITAL
SERVO
SUBCODE
SEPARATION
Q CRC
MICROPROCESSOR
INTERFACE
Slice level
control
VCO clock Oscillator
Clock control
SYNCHRONIZATION
DETECTION
EFM DEMODULATION
SERVO
COMMAND
Digital
output
1bit DAC
10
9
6
3
5
21
2
69
37
80
12
26
31
74
27
42
45
8
4
44
56
38
39
40
41
36
34
33
46
48
49
52
53
55
43
77
62
58
73
75
70
32
23,29
20,28
68,19
16,17
18
30
64
66
67
63,65
57,60
59,61
15
14
13
22
11
1
24,25
72
71
78
76,79
51,54
47,50
35
17
IC BLOCK DIAGRAM
U101: LA9240
U301: LC78621ED
18
U302: PCM1710U
Input
Interface
Timing
Control
Digital
Filter
Mode
Control
Noise
Shaper
5-Level DAC
Left
Low Pass Filter
Left
CMOS Amp
Left
5-Level DAC
Right
Low Pass Filter
Right
CMOS Amp
Right
1
2
3
4
6
8
10
12
5
7
9
11
13
14
LRCIN
DIN
BCKIN
CLKO
XTI
XTO
DGND
VDD
VCC2R
AGND2R
EXT1R
EXT2R
VOUTR
AGND1
28
27
26
25
23
21
19
17
24
22
20
18
16
15
ML/DSD
MC/DM2
MC/DM1
MUTE
MODE
CKSL
DGND
VDD
VCC2L
AGND2L
EXT1L
EXT2L
VOUTL
VCC1
A1
B1
Y1
A2
B2
Y2
GND
VCC
B4
A4
Y4
B3
A3
Y3
1
2
3
4
5
6
7
14
13
12
11
10
9
8
AMPLIFIER 1
OUTPUT
INVERTING
INPUT
NON-INVERTING
INPUT
V –
AMPLIFIER 2
V +
OUTPUT
INVERTING
INPUT
NON-INVERTING
INPUT
1
2
3
4
8
7
6
5
+ –– +
U305-U306: NE5532
U403: TC74HC00
1
VCC
2
MUTE
3
V IN1
4
VG 1
5
Vo1
6
Vo2
7
GND
8
GND
9
GND
10
Vo3
11
Vo4
12
VG2
13
V IN2
14
REG OUT
15
REG IN
30 VCC
29 V REF
28 V IN4
27 VG 4
26 Vo8
25 Vo7
24 GND
23 GND
22 GND
21 Vo6
20 Vo5
19 VG3
18 V IN3
17 CD
16 RES
Level shift
4
Level shift
1
BTL AMP
4
BTL AMP
1
11K11K
11K11K
Vcc
BTL AMP
3
BTL AMP
2
Level Shift
3
Level Shift
2
Regulator RESET
19
U201: LA6541D
P1 OUT1 VCC2 OUT2 P2
3281097
4
5
1
6
VCC1
VZ
IN1
GND
IN2
Predriver
Input logic circuit
U701: LB1641
20
SEG13
SEG12
SEG11
SEG10
SEG09
SEG08
SEG07
SEG06
SEG05
SEG04
SEG03
SEG02
TST
SEG01
M4
M3
RES
INT
S01
S02
S03
S04
P1
P2
P3
P4
XTOUT
XTIN
VDD1
VDD2
VSS
VDD
N2
N1
M4
M3
M2
M1
K4
K3
K2
K1
S4
S3
S2
S1
CFOUT
CFIN
SEG14
SEG15
SEG16
SEG17
SEG18
SEG19
SEG20
SEG21
SEG22
SEG23
COM4
COM3
COM2
COM1
CUP1
CUP2
48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
ROM S port
K port
M port
SO port
P port
OSC1
OSC2
Reset function
N port
Carrier control circuit
8-bit reload timer
(timer 2)
8-bit preset timer
(timer 2)
Serial interface
Base timer (free-
running timer)
Alarm signal
generator
Watchdog timer
PC
OPG
APG
DPF
STACK
DP
BNK
RAM
ACC
ALU
Breg
Insert
Stand by
Data decoder
Segment RLA
LCD driver
Segment pins
Common pins
Strobe decoder
Table reference function
Note: Shaded blocks can be selected
by the user as mask options.
U401: LC587206A
21
TROUBLESHOOTING GUIDE
SET POWER SWITCH TO ON.
IS POWER TURNED ON ?
M502, M503, M504, M505
DEFECTIVE
CRYSTAL M401 DEFECTIVE.
MICROPROCESSOR IC U401 DEFECTIVE.
MOTOR DRIVE IC U701 DEFECTIVE.
CAN TRAY BE OPENED ?
CAN TRAY BE CLOSED ?
DOES INITIAL READING OCCUR ?
CAN DISC BE PLAYED ? CHECK TRACKING SERVO CIRCUIT CORRECT ? SERVO IC U101 OR U201 DEFECTIVE.
CHECK DISC OR MECHANISM AND CONNECTOR
CHECK OUTPUT PULSE AT PIN 42,43,44 OF U301
CHECK OUTPUT SIGNAL AT PIN 13,16 OF U302
AUDIO OUTPUT IS CORRECT ? IS POWER SUPPLY NORMALLY ? CHECK POWER SUPPLY PATTERNS.
OK
CHECK POWER SUPPLY
CIRCUIT NORMAL ?
CHECK FUSES M502, M503,
M504, M505 OPEN ?
IC U302 DEFECTIVE.
CHECK OUTPUT SIGNAL AT PIN 1,7 OF U305, U306 IC U305 OR U306 DEFECTIVE.
CHECK OUTPUT SIGNAL AT PIN 7,1 OF U305, U306 IC U305 OR U306 DEFECTIVE.
CHECK MUTE CIRCUIT Q301, Q302, Q303, Q304
LINE OUT PLUG OR PATTERNS DEFECTIVE.
MUTE CIRCUIT DEFECTIVE.
IC U301 DEFECTIVE.
M101 SWITCH, DEFECTIVE
OR PATTERN AND CONNECTOR OPEN.
IS OSCILLATOR CIRCUIT
OSCILLATING ?
POWER SUPPLY PATTERNS OPEN
OR U501-U504,U506-U507 DEFECTIVE.
IS THERE OPEN/ CLOSE KEY SIGNAL
INPUT ? U401 PIN 21,22
IS LOADING MOTOR DRIVE CIRCUIT
OPERATION NORMAL ? U701, PIN 2,10
CHECK OPEN/ CLOSE SIGNAL AT U401
PIN 21 PIN 22
TRAY OPEN H L
TRAY CLOSE L H
LOADING MOTOR AND LEAD WIRE DEFECTIVE
OR LOADING PART OF MECHANISM DEFECTIVE.
CHECK LASER LIGHT ? DOES LENS MOVE UP AND DOWN ?
RF SIGNAL OUTPUT ?
U101 DEFECTIVE.
FEED MOTOR OR WIRING DEFECTIVE.
CHECK FOCUS SIGNAL OUTPUT ?
U101 DEFECTIVE.
CHECK CONNECTION OR PICKUP.
CHECK LASER CIRCUIT CORRECT ?
CONNECTION OR PICKUP DEFECTIVE.
YES
YES
YES
YES
YES
YES
YES
YESNO
NO
NO
NO
YES
YES
YES YES YES
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO NO NO
NO
NONO
NO
NO
NO NO
NO
NO
NO
CHECK CLOCK PULSE AT PIN4 OF U302 M302 OR U302 DEFECTIVE.
YES
NO
NO
NO
NO
NO
NO
27
MECHANISM EXPLODED VIEW
CD11CA
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