Mitsubishi Electric DD-8020 User manual

MITSUBISHI DIGITAL ELECTRONICS AMERICA, INC.
9351 Jeronimo Rd. Irvine, CA 92618
Copyright © 2002 Mitsubishi Digital Electronics America, Inc.
All Rights Reserved
Operating conditions: Temperature: 5°C to 35°C
Operation status: Horizontal
Video output: 1.0 V (p-p), 75Ω, negative
sync., pin jack x 1
S Video output: (Y) 1.0 V (p-p), 75Ω, nega-
tive sync., Mini DIN 4-pin x 1
(C) 0.286 V (p-p), 75Ω
Color Difference outputs: (Y) 1.0 V (p-p), 75Ω,
(1 Interlaced) negative sync., pin jack x 1
(1 Progressive) (Cr, Pr)/(Cb, Pb) 0.7 V (p-p),
75Ω, pin jack x 2
Digital Audio output: (Bitstream/PCM) 0.5 V (p-p),
75Ω, pin jack x 1,
Optical connector x 1
Analog Audio output: 2.0 V (rms), 220Ω, pin jack
2 CH L R x 2,
5.1 CH SURROUND x 6
CAUTION
Before servicing this chassis, it is important that the service person reads all SAFETY PRECAUTIONS and the
SAFETY NOTICE in this manual.
SPECIFICATIONS
Power Supply: 120V AC, 60 Hz
Power Consumption: 17W
Weight: 6.6 lb.
External Dimensions: 17"x 3-3/8"x12-1/8"
(W/H/D)
Signal System: Standard NTSC
Laser: Semiconductor laser,
wavelength 650nm/780nm
Frequency Range: (Digital Audio)
DVD Linear -
48 kHZ Sampling: 4 Hz to 22 kHz
96 kHZ Sampling: 4 Hz to 44 kHz
Signal-To-Noise Ratio: More than 112 dB (EIAJ)
Audio Dynamic Range: More than 108 dB (EIAJ)
Harmonic Distortion: Less than 0.002%
Wow and flutter: Below measurable level
(less than ± 0.001%
(W.PEAK)) (EIAJ)
SerSer
SerSer
Servicevice
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ManualManual
ManualManual
Manual
2002
MITSUBISH ELECTRIC
Model
DD-8020
DVD Player
OPEN/CLOSE
STOP PLAY PAUSE/STEP
POWER
DVD AUDIO/VIDEO PLAYER DD-8020
STANDBY
SKIP
REV FWD
/
CDVD
TITLETRK CHP TOTAL REMAIN MEMORY
HDCD
PROGRESSIVE
AUDIO

-

SAFETY NOTICE
SAFETY PRECAUTIONS
LEAKAGE CURRENT CHECK
Plug the AC line cord directly into a 120VAC outlet (do
not use an isolation transformer for this check). Use an
AC voltmeter, having 5000 Ωper volt or more sensitivity.
Connect a 1500 Ω10 W resistor, paralleled by a 0.15 µF
150VAC capacitor between a known good earth ground
(water pipe, conduit, etc.) and all exposed metal parts of
cabinet (antennas, handle bracket, metal cabinet
screwheads, metal overlays, control shafts, etc.).
Measure theAC voltage across the 1500 Ωresistor.
The test must be conducted with the AC switch on and
then repeated with the AC switch off. TheAC voltage
indicated by the meter may not exceed 0.3 V.A reading
exceeding 0.3 V indicates that a dangerous potential
exists, the fault must be located and corrected.
Repeat the above test with the DVD VIDEO PLAYER
power plug reversed.
NEVER RETURN A DVD VIDEO PLAYER TO THE
CUSTOMER WITHOUT TAKING NECESSARY
CORRECTIVE ACTION.
READING SHOULD NOT EXCEED 0.3V
DVD VIDEO PLAYER AC VOLTMETER
(5000 W per volt
or more sensitivity)
Good earth ground
such as a water pipe,
conduit, etc.
1500 W
10 W
0.15 µF 150V AC
AC OUTLET
Test all exposed metal.
Voltmeter Hook-up for Leakage Current Check

LASER BEAM CAUTION LABEL
When the power supply is turned on, you may not remove this laser caution label. If it is removed, laser radiation
may be recceived.
The lightning flash with arrowhead symbol, within an
equilateral triangle, is intended to alert the user to the
presence of uninsulated “dangerous voltage” within the
product’s enclosure that may be of sufficient magnitude to
constitute a risk of electric shock to persons.
The exclamation point within an equilateral triangle is
intended to alert the user to the presence of important
operating and maintenance (servicing) instructions in the
literature accompanying the appliance.
SAFETY NOTICE

SECTION 2
PART REPLACEMENT AND ADJUSTMENT PROCEDURES
SECTION 3
SERVICING DIAGRAMS
1. STANDING PC BOARDS FOR SERVICING ..................... 3-1
2. CIRCUIT SYMBOLS AND
SUPPLEMENTARY EXPLANATION ..................................... 3-2
2-1. Precautions for Part Replacement .................................... 3-2
2-2. Solid Resistor Indication .................................................... 3-2
2-3. Capacitance Indication ....................................................... 3-2
2-4. Inductor Indication ............................................................. 3-3
2-5. Waveform and Voltage Measurement .............................. 3-3
3. PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM .......................................................... 3-5
4. BLOCK DIAGRAMS .................................................................. 3-7
4-1. Overall Block Diagram ...................................................... 3-7
4-2. Power Supply Block Diagram ........................................... 3-9
4-3. Front Display, Power Switch Block Diagram ................ 3-10
4-4. Main Block Diagrams .................................................... 3-13
4-5. Output Block Diagram .................................................. 3-17
5. CIRCUIT DIAGRAMS ........................................................... 3-19
5-1. Power Supply Circuit Diagram .................................... 3-19
5-2. Front Display, Power Switch Circuit Diagram ......... 3-21
5-3. Main Circuit Diagram ................................................... 3-24
5-4. Output Circuit Diagram ................................................ 3-29
5-5. Motor System Circuit Diagrams .................................. 3-34
6. PC BOARDS ............................................................................ 3-35
6-1. Power Supply PC Board ................................................ 3-35
6-2. Main PC Board ............................................................... 3-37
6-3. Output PC Board ............................................................ 3-47
CONTENTS
SECTION 1
GENERAL DESCRIPTIONS
1. PREPARATION FOR SERVICING ......................................... 1-1
2. LOCATION OF MAIN PARTS AND
MECHANISM PARTS ............................................................... 1-2
2-1. Location of Main Parts ....................................................... 1-2
2-2. Location of Mechanism Parts ............................................ 1-3
1. REPLACEMENT OF MECHANICAL PARTS ................... 2-1
1-1. Cabinet Replacement ....................................................... 2-1
1-1-1. Top Cover ...................................................................... 2-1
1-1-2. Clamper Stay ................................................................ 2-1
1-1-3. Tray Panel ..................................................................... 2-2
1-1-4. Front Panel and Tray .................................................. 2-3
1-1-5. Rear Panel ..................................................................... 2-3
1-2. PC Board Replacement ................................................... 2-4
1-2-1. Main PC Board ............................................................. 2-4
1-2-2. Output PC Board ......................................................... 2-4
1-2-3. Power PC board ........................................................... 2-5
1-2-4. Front PC Board ............................................................ 2-5
1-3. Mechanism Parts ............................................................... 2-6
1-3-1. Mechanism Chassis Assembly ..................................... 2-6
1-3-2. Loading Belt .................................................................. 2-6
1-3-3. Loading Motor .............................................................. 2-7
1-3-4. Sub Chassis (with a pickup mechanism) ................... 2-7
1-3-5. Pickup Mechanism Assembly ...................................... 2-8
1-3-6. Gear A Assembly, Gear B and
Rack Gear Assembly ...................................................... 2-8
1-3-7. Feed Motor ...................................................................... 2-9
3. TROUBLESHOOTING ............................................................ 1-7
3-1. Main Circuit ....................................................................... 1 -7
3-1-1. Servo System ................................................................. 1-7
3-1-2. Location Diagram of Servo Test Point .................. 1-14
SECTION 4
PARTS LIST
SAFETY PRECAUTION ............................................................... 4-1
NOTICE ............................................................................................ 4-1
ABBREVIATIONS .......................................................................... 4-1
1. Integrated Circuit (IC) ........................................................ 4-1
2. Capacitor (Cap) .................................................................... 4-1
3. Resistor (Res) ......................................................................... 4-1
4. EXPLODED VIEWS ................................................................. 4-2
4-1. Packing Assembly ............................................................. 4-2
4-2. Chassis Assembly ............................................................... 4-3
4-3. Mechanism Assembly ........................................................ 4-4
5. PARTS LIST ............................................................................... 4-6

-

SECTION 1
GENERAL DESCRIPTIONS
SECTION 1
GENERAL DESCRIPTIONS
1MΩ
Ground conductive
wrist strap for body.
S
oldering iron
with ground wire
or ceramic type
Conductive mat The ground resistance
between the ground line
and the ground is less than 10Ω.
The Pickup Head consists of a laser diode that is very susceptible to external static electricity.
Although it may operate properly after replacement, if subjected to electrostatic discharge during replacement,
its life might be shortened. When replacing the laser diode, LSI's and IC's, use a conductive mat, soldering iron
with ground wire, etc. to protect against damage from static electricity.
1. PREPARATION FOR SERVICING
GENERAL DESCRIPTIONS
1-1

2. LOCATION OF MAIN PARTS AND MECHANISM PARTS
2-1. Location of Main Parts
Fig. 1-2-1
EU05 Output PC board
Feed motor PC board
EU03 Front display PC board
Loading motor PC board
Disc motor PC board
EU04 Power W PC board
EU01 Main PC board
EU02 Power supply PC board
1-2

2-2. Location of Mechanism Parts
Fig. 1-2-2 Mechanism chassis assembly (Top side)
Fig. 1-2-3 Mechanism chassis assembly (Bottom side)
Tra
y
Clamper sta
y
Loading moto
r
PC board
Mechanism chassis
1-3

Fig. 1-2-4 Mechanism chassis assembly (Internal side)
Loading belt
Loading motor
Kick lever
Cam Slide
r
Gea
r
Gea
r
Gea
r
Disc motor
1-4

Fig. 1-2-5 Pickup mechanism chassis assembly (Top side)
Fig. 1-2-6 Pickup mechanism chassis assembly (Bottom side)
Front damper
Rack gear
assembly
Gear
Gear B assembly
Front dampe
r
Sub chassis
Rear dampe
r
Pickup assembly
Rear damper
Feed moto
r
Feed moto
r
PC boar
d
<Type A>
Note:
When servicing, note that this model has two types of
pickup mechanism assembly.
Type Ais a service part. Type B can be replaced with a Type A pickup.
1-5

<Type B>
Fig. 1-2-7 Pickup mechanism chassis assembly (Top side)
Fig. 1-2-8 Pickup mechanism chassis assembly (Bottom side)
Front damper
Rack gear
assembly
Gear
Gear B assembly
Front dampe
r
Sub chassis
Rear dampe
r
Pickup assembly
Rear damper
Feed moto
r
Feed moto
r
PC boar
d
1-6

3. TROUBLESHOOTING
3-1. Main Circuit
3-1-1. Servo System
(1) Initial Operation after Power ON
Power ON
end each L I hard R T
command and initial command.
Pickup head is positioned at
transmission initial position.
Is tray closed?
Pin 5 of CN502,
TCL =L
Disc presence/absence and
disc judgement
Is a disc present?
DVD or CD initial setting.
DVD single
Initial setting.
DVD dual
Initial setting.
CD
Initial setting.
To each disc playback process.
DVD single (single-layer) DVD single
(single-layer)/DVD dual
(dual-layer)/CD?
CD
DVD dual (dual-layer)
1
Tray close operation
Pin C9 of IC306 (E537): LDMP = H/L
Pin Y19 of IC306 (E538): LDMN = L
Is tray closed?
Pin 5 of CN502:
TCL = L
Y
N
Tray stops.
Pin C9 of IC306 : LDMP = H
Pin Y19 of IC306 : LDMN = L
Laser OFF
Display: IN ERT DI C
Monitor screen: NO DI C
Y
Y
NG
N
N
2
Fig. 1-3-1
1-7

Pickup (P.U.) transmission initial
operation does not occur.
The pickup transmission initial operation is carried out to
determine the initial position by transmitting the pickup to the
innermost position once (start-limit switch (pin 4 of C 503)
develops "L".) and to the external direction at low speed
(start-limit switch develops "H", turning off the switch.).
1
Does pulse of
1.65V 1.65V develop at
pin 162 of IC401?
Check BUS between IC401-IC306
and oscillation.
Check feed gear.
Y
2-1
" o disc" misjudgement display of
disc presence.
Does lens move with
UP/DOW full stroke in
focus direction?
Is laser current normal?
Check IC401.
Does search signal
output at both edges of focus coil?
(Pins 15 to 18 of C 501)
Does focus search
voltage of 1.65V 0.4V develop
at pin 23 of IC503 (E544)?
Check pickup head
and wiring.
Does RFSB signal
develop more than 0.3V?
Check IC502.
Lens cleaning.
Replace pickup head.
Check peripheral
circuit of IC306.
Check IC503.
Y
Y
Y
Y
3
Y
Fig. 1-3-2
Fig. 1-3-3
1-8

Disc kind misjudgement
(Initial setting is G.)
Replace pickup head.
Lens cleaning.
Check IC502.
Are FE and RFSB
signals for each disc normal?
Check peripheral
circuit of IC306.
2-2
Y
Check laser operating current.
Check laser current.
I min lop I max
Check pins 13, 14
and 15 of IC502
serial bus.
Check peripheral
circuits of IC502,
Q501, Q502.
Check solder removal
of the short land for
laser diode protection.
Check FE and RFSB signal
lop I max
lop I min
3
Check wiring for
pickup head.
Replace pickup
mechanism.
Y
Y
lop 200 mA
Laser operating current
DVD Iop
DVD Iop = Voltage between (E559 and E534) /10 W
CD Iop = Voltage between (E536 and E534) /10 W
CD Iop
min
20mA
20mA
35mA
45mA
60mA
80mA
typ max
CAUTIO
The laser ray emitting out from the pickup head is very harmful to your eyes.
Keep your eyes from the objective lens at least 300mm distance during the pickup head operating.
When you perform solder removal work, please turn OFF a set power supply and perform the
ground of human body and a tool.
To turn on each laser diode forcibly, press the following buttons on the remote controller.
DVD LD:
CD LD:
After checked the laser current, press POWER or OPE /CLOSE button to turn it off.
ZOOM, 0, 3, 0, ZOOM
ZOOM, 0, 3, 1, ZOOM
Fig. 1-3-4
Fig. 1-3-5
TP405 FE signal
1.65V
V : 500 mV/div
H : 2 ms/div
TP503 RFSB signal
DVD single (single-layer) disc
detection waveform
V : 500 mV/div
H : 2 ms/div
DVD dual (dual-layer) disc
detection waveform
V : 500 mV/div
H : 2 ms/div
CD disc
detection waveform
Fig. 1-3-6 Fig. 1-3-7 Fig. 1-3-8
1-9

Disc motor (D.M.) forced
accelleration (500 ms)
Focus search
PLAY
Is forcus servo
ON?
CLV servo ON.
Tracking balance adjustment
Tracking servo ON.
Focus gain adjustment
Tracking gain adjustment
Focus balance adjustment
RF gain adjustment
Repeat three times.
Is address code
possible to read?
Search Picture appears.
Does NG continue
more than 3 s.?
Disc playback NG
4
2-1 5
4
6
Y
N
N
Y
Y
:
Automatic adjustment is carried
out when a disc is replaced after
power ON.
N
N
N
Y
Y
N
N
Y
Y
Fig. 1-3-9
(2) Picture appears (PLAY)
1-10

4
Disc motor (D.M.) does not rotate.
Does pin 117 of IC401
(TP409) PLCK oscillate around
10 MHz ?
Check peripheral
circuit of IC402.
Check peripheral circuits
of IC402.
Check disc motor and wiring.
N
Y
Focus servo is G.
Are FE, RFSB,
FSO signals normal?
Check peripheral circuit of IC306.
Do signals output to
pins 9 to 14 of C 501?
Check IC502.
Check wiring for
pickup head.
Lens cleaning.
Replace pickup
mechanism.
Y
Y
5
FE signal
Pin 150 (TP405)
of IC401
RFSB signal
Pin 152 (TP503)
of IC401
0.3V
1.65V
0.3V
Focus search Focus servo on
Focus servo ON
signal waveform
Fig. 1-3-10
Fig. 1-3-11
Fig. 1-3-12
1-11

Tracking servo is NG.
Is TE signal normal?
Check peripheral
circuit of IC306.
Check IC502.
6
Y
N
Signal waveform at
tracking servo ON (CD)
TE signal
Pin 151 (TP406) of IC401
1.65V
RFRP signal
Pin 153 (TP408) of IC401
Search ON (SRCH)
Pin 38 (TP411) of IC401
ON search Tracking servo on
Signal waveform at
tracking servo ON (DVD)
Fig. 1-3-13
Fig. 1-3-14
Fig. 1-3-15
1-12

Disc playback is NG (DVD).
Is PLL locked?
(Refer to waveforms.)
Check signal process
system following to IC402.
Check peripheral circuits
of IC401 and IC306.
Does pulse of
L = 1.65V and H = 3.3V
develop at pin 131 and
L = 0V and H = 1.65V
develop at pin 132
of IC401?
Does RF output
higher than 1 V(p-p)
develop at pin 30 (TP502)
of IC502?
Check IC502.
Lens cleaning.
Pickup mechanism
replacement
Check peripheral circuits of
IC401 and IC306.
Pin 43 of IC502 = 2.4V
Pin 44 of IC502 = 3.0V
Check peripheral circuits
of IC502 and IC401.
7
Y
N
N
N
N
Y
Y
Y
DVD RF signal
Pin 30 (TP502) of IC502
V : 500 mV/div
H : 50 ns/div
DVD RF signal
DVD RF signal
Pin 30 (TP502) of IC502
DVD PLCK
Pin 117 (TP409) of IC401
CH1 : TP502 DVDRF 500 mV/div
CH2 : TP409 DVDPLCK 5 V/div
50 ns/div
DVD playback waveform
CD RF signal
Pin 30 (TP502) of IC502
V : 500 mV/div
H : 100 ns/div
CD RF signal
CD RF signal
Pin 30 (TP502) of IC502
CD PLCK
Pin 117 (TP409) of IC401
CH1 : TP502 CDRF 500 mV/div
CH2 : TP409 CDPLCK 5 V/div
100 ns/div
CD playback waveform
Fig. 1-3-16
Fig. 1-3-17
Fig. 1-3-19
Fig. 1-3-18
Fig. 1-3-20
PLL works as a servo loop to generate a clock signal for reading RF
signal binary data. With the PLL locked, the eye pattern is identified
clearly when triggered with the read clock PLCK.
1-13

Fig. 1-3-21
3-1-2. Location Diagram of Servo Test Point
C 503
C 501
C 701
C 901
C 302
C 601
C 603
C 502
IC503 IC502
IC313
IC312
IC401
IC306
TP502 RFO
E559 DVD
E538 LDM
E544 FOO
E534 +5V
E536 CD
E537 LDMP
TP405 FE
TP504 RFCT
TP406 TE
TP401 VRFED
TP408 RFRP
TP410 FLGA
TP411 FLGB
TP409 PLCK
TP412 VMCK
TP503 RFSB
1-14