Mitsubishi DD-8020 Service manual

2002

MITSUBISH ELECTRIC

POWER

DVD AUDIO/VIDEO PLAYER

STANDBY

DD-8020

TITLETRK CHP TOTAL REMAIN MEMORY

AUDIO

HDCD

CDVD

SerSer

Ser

SerSer
ManualManual

Manual

ManualManual

vicevice

vice

vicevice

DVD Player

Model

DD-8020

OPEN/CLOSE

PROGRESSIVE

STOP PLAY PAUSE/STEP

REV

FWD

/

SKIP

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)

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

MITSUBISHI DIGITAL ELECTRONICS AMERICA, INC.

9351 Jeronimo Rd. Irvine, CA 92618

Copyright © 2002 Mitsubishi Digital Electronics America, Inc.

All Rights Reserved

-

SAFETY NOTICE

SAFETY PRECAUTIONS

LEAKAGE CURRENT CHECK

Plug the AC line cord directly into a 120V AC outlet (do
not use an isolation transformer for this check). Use an
AC voltmeter, having 5000 Ω per volt or more sensitivity.

Connect a 1500 Ω 10 W resistor, paralleled by a 0.15 µF
150V AC 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.).

READING SHOULD NOT EXCEED 0.3V

Measure the AC voltage across the 1500 Ω resistor.
The test must be conducted with the AC switch on and

then repeated with the AC switch off. The AC 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 T AKING NECESSAR Y
CORRECTIVE ACTION.

DVD VIDEO PLAYER

AC OUTLET

Test all exposed metal.
Voltmeter Hook-up for Leakage Current Check

1500

W

10 W

0.15 µF 150V AC

AC VOLTMETER

(5000 W per volt
or more sensitivity)

Good earth ground
such as a water pipe,
conduit, etc.

SAFETY NOTICE

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.

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.

CONTENTS

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

SECTION 1

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

PART REPLACEMENT AND ADJUSTMENT PROCEDURES

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

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

SECTION 2

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

SECTION 3

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

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

SECTION 4

PARTS LIST

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

-

GENERAL DESCRIPTIONS

S

GENERAL DESCRIPTIONS

SECTION 1

GENERAL DESCRIPTIONS

1. PREPARATION FOR SERVICING

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.

Ground conductive
wrist strap for body.

oldering iron
with ground wire
or ceramic type

SECTION 1

1MΩ

Conductive mat

The ground resistance
between the ground line
and the ground is less than 10Ω.

1-1

2. LOCATION OF MAIN PARTS AND MECHANISM PARTS

2-1. Location of Main Parts

Feed motor PC board

EU02 Power supply PC board

EU04 Power SW PC board

Disc motor PC board

EU01 Main PC board

EU05 Output PC board

Loading motor PC board

EU03 Front display PC board

Fig. 1-2-1

1-2

2-2. Location of Mechanism Parts

y

y

r

Tra

Clamper sta

Fig. 1-2-2 Mechanism chassis assembly (Top side)

Loading moto

PC board

Mechanism chassis

Fig. 1-2-3 Mechanism chassis assembly (Bottom side)

1-3

Loading belt

r

r

r

r

Gea

Kick lever

Loading motor

Disc motor

Gea

Gea

Cam Slide

Fig. 1-2-4 Mechanism chassis assembly (Internal side)

1-4

r

r

r

r

d

<Type A>

Note:

When servicing, note that this model has two types of
pickup mechanism assembly.

Type A is a service part. Type B can be replaced with a Type A pickup.

Front damper

Rack gear
assembly

Gear A

Gear B assembly

Rear damper

Front dampe

Pickup assembly

Sub chassis

Rear dampe

Fig. 1-2-5 Pickup mechanism chassis assembly (Top side)

Fig. 1-2-6 Pickup mechanism chassis assembly (Bottom side)

1-5

Feed moto

Feed moto

PC boar

<Type B>

r

r

r

r

d

Front damper

Rack gear
assembly

Gear A

Gear B assembly

Rear damper

Front dampe

Pickup assembly

Sub chassis

Rear dampe

Fig. 1-2-7 Pickup mechanism chassis assembly (Top side)

Fig. 1-2-8 Pickup mechanism chassis assembly (Bottom side)

1-6

Feed moto

Feed moto

PC boar

3. TROUBLESHOOTING

3-1. Main Circuit

3-1-1. Servo System

(1) Initial Operation after Power ON

Power ON

Send each LSI hard RST
command and initial command.

Pickup head is positioned at
transmission initial position.

Is tray closed?

Pin 5 of CN502,

TCLS=L

Y

2

NG

Disc presence/absence and
disc judgement

Is a disc present?

Y

DVD or CD initial setting.

N

Tray close operation
Pin C9 of IC306 (E537): LDMP = H/L
Pin Y19 of IC306 (E538): LDMN = L

Tray stops.
Pin C9 of IC306 : LDMP = H
Pin Y19 of IC306 : LDMN = L

N

Laser OFF
Display: INSERT DISC
Monitor screen: NO DISC

1

Is tray closed?

Pin 5 of CN502:

TCLS = L

Y

N

DVD single (single-layer)

DVD single
Initial setting.

DVD single

(single-layer)/DVD dual

(dual-layer)/CD?

DVD dual (dual-layer)

DVD dual
Initial setting.

To each disc playback process.

Fig. 1-3-1

1-7

CD

CD
Initial setting.

1

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 CN503)
develops "L".) and to the external direction at low speed
(start-limit switch develops "H", turning off the switch.).

Does pulse of

1.65V 1.65V develop at
pin 162 of IC401?

Y

Check feed gear.

N

Check BUS between IC401-IC306
and oscillation.

Fig. 1-3-2

2-1

"No disc" misjudgement display of

N

disc presence.

Does lens move with

UP/DOWN full stroke in

focus direction?

Y

N

3

Does focus search

voltage of 1.65V 0.4V develop

at pin 23 of IC503 (E544)?

Y

Does search signal

output at both edges of focus coil?

(Pins 15 to 18 of CN501)

Y

Check pickup head
and wiring.

Is laser current normal?

Y

Does RFSB signal

develop more than 0.3V?

Y

Check peripheral
circuit of IC306.

N

N

Check IC401.

Check IC503.

Fig. 1-3-3

N

Check IC502.

Lens cleaning.

Replace pickup head.

1-8

2-2

V : 500 mV/div
H : 2 ms/div

CD disc

detection waveform

Disc kind misjudgement

(Initial setting is NG.)

N

Check IC502.

Lens cleaning.

Replace pickup head.

Are FE and RFSB

signals for each disc normal?

Y

Check peripheral
circuit of IC306.

Fig. 1-3-4

3

DVD Iop

Check laser operating current.

lop I min

Check wiring for
pickup head.

Check pins 13, 14
and 15 of IC502
serial bus.

Check peripheral
circuits of IC502,
Q501, Q502.

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 OPEN/CLOSE button to turn it off.

CAUTION
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.

ZOOM, 0, 3, 0, ZOOM
ZOOM, 0, 3, 1, ZOOM

Check laser current.
I min lop I max

Y

Check FE and RFSB signal

lop I max

Check solder removal
of the short land for
laser diode protection.

CD Iop

DVD Iop = Voltage between (E559 and E534) /10

CD Iop = Voltage between (E536 and E534) /10

lop 200 mA

Y

Laser operating current

min

typ max

20mA

35mA

60mA

20mA

45mA

80mA

N

Replace pickup

mechanism.

W
W

DVD single (single-layer) disc

detection waveform

Fig. 1-3-5

DVD dual (dual-layer) disc

detection waveform

TP405 FE signal

1.65V

TP503 RFSB signal

V : 500 mV/div
H : 2 ms/div

V : 500 mV/div
H : 2 ms/div

Fig. 1-3-6 Fig. 1-3-7 Fig. 1-3-8

1-9

(2) Picture appears (PLAY)

PLAY

4

2-1

N

N

Disc motor (D.M.) forced

accelleration (500 ms)

Focus search

Is forcus servo

CLV servo ON.

Tracking balance adjustment

Tracking servo ON.

Focus gain adjustment

Tracking gain adjustment

Y

Y

Y

Y

Y

ON?

Repeat three times.

N

N

N

:

Automatic adjustment is carried
out when a disc is replaced after
power ON.

5

4

6

Focus balance adjustment

RF gain adjustment

N

N

Does NG continue

more than 3 s.?

Y

Disc playback NG

Is address code

possible to read?

Y

Search Picture appears.

Fig. 1-3-9

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

Do signals output to

pins 9 to 14 of CN501?

Y

Check IC502.

5

Focus servo is NG.

N

N

Are FE, RFSB,

FSON signals normal?

Y

Check peripheral circuit of IC306.

Check wiring for

pickup head.

Lens cleaning.

Replace pickup

mechanism.

Fig. 1-3-10

Focus servo ON

signal waveform

Focus search Focus servo on

Fig. 1-3-12

FE signal
Pin 150 (TP405)
of IC401

0.3V

1.65V

0.3V

RFSB signal
Pin 152 (TP503)
of IC401

Fig. 1-3-11

1-11

6

Signal waveform at

tracking servo ON (DVD)

Tracking servo is NG.

Signal waveform at

tracking servo ON (CD)

Check IC502.

TE signal
Pin 151 (TP406) of IC401

1.65V

RFRP signal
Pin 153 (TP408) of IC401

N

Is TE signal normal?

Y

Check peripheral

circuit of IC306.

Fig. 1-3-13

ON search Tracking servo on

Search ON (SRCH)
Pin 38 (TP411) of IC401

Fig. 1-3-15

Fig. 1-3-14

1-12

7

Disc playback is NG (DVD).

Is PLL locked?

(Refer to waveforms.)

Y

Check signal process
system following to IC402.

N

Check peripheral circuits of
IC401 and IC306.

N

Fig. 1-3-16

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?

Y

Does RF output

higher than 1 V(p-p)

develop at pin 30 (TP502)

of IC502?

Y

Pin 43 of IC502 = 2.4V
Pin 44 of IC502 = 3.0V

Y

Check peripheral circuits
of IC502 and IC401.

N

Check peripheral circuits
of IC401 and IC306.

N

Check IC502.

Lens cleaning.

Pickup mechanism

replacement

DVD RF signal

Fig. 1-3-17

CD RF signal

DVD RF signal
Pin 30 (TP502) of IC502

V : 500 mV/div
H : 50 ns/div

CD RF signal
Pin 30 (TP502) of IC502

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.

DVD playback waveform

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

Fig. 1-3-19

CD playback waveform

CD RF signal
Pin 30 (TP502) of IC502

Fig. 1-3-18

V : 500 mV/div
H : 100 ns/div

1-13

CH1 : TP502 CDRF 500 mV/div
CH2 : TP409 CDPLCK 5 V/div

100 ns/div

Fig. 1-3-20

CD PLCK
Pin 117 (TP409) of IC401

3-1-2. Location Diagram of Servo Test Point

E536 CD

E534 +5V

E538 LDMN

E544 FOO

E537 LDMP

CN502

CN603

IC503

CN503

IC401

IC502

CN501

IC313

IC312

E559 DVD

TP502 RFO

CN701

CN901

IC306

TP401 VRFED

TP408 RFRP

TP410 FLGA

TP411 FLGB

CN302

CN601

TP504 RFCT

TP405 FE

TP406 TE

TP503 RFSB

TP409 PLCK

TP412 VMCK

Fig. 1-3-21

1-14

SECTION 2

PART REPLACEMENT AND

ADJUSTMENT PROCEDURES

CAUTIONS BEFORE STARTING SERVICING

Electronic parts are susceptible to static electricity and may easily damaged, so do not forget to take a proper grounding
treatment as required.

Many screws are used inside the unit. To prevent missing, dropping, etc. of the screws, always use a magnetized screw­driver in servicing. Several kinds of screws are used and some of them need special cautions. That is, take care of the
tapping screws securing molded parts and fine pitch screws used to secure metal parts. If they are used improperly, the
screw holes will be easily damaged and the parts can not be fixed.

1. REPLACEMENT OF MECHANICAL PARTS

1-1. Cabinet Replacement

1-1-1. Top Cover

1. Remove five screws (1) and remove the top cover (2).

Screw (1)

Top cover (2)

Screws (1)

Screw (1)

1-1-2. Clamper Stay

<Removal>

1. Remove two screws (1).

2. Release two claws and remove the clamper stay (2).

Screws (1)

Clamper stay (2)

Clamper
stay (2)

Claw

A

Clamper stay (2)

Claw

Fig. 2-1-1

2-1

Spring

Claws

Fig. 2-1-2