LG MDT505 Diagram

MODEL: MDT505(MDS505V/W)SERVICE MANUAL

Internal Use Only

Website http://biz.lgservice.com

MINI HOME THEATER

SERVICE MANUAL

MODEL:

CAUTION

BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.

0102,SEPTEMBER21827947NFA:ON/P

MDT505 (MDS505V/W)

CONTENTS

SECTION 1 ........ GENERAL

SECTION 2 ........ CABINET & MAIN CHASSIS

SECTION 3 ........ ELECTRICAL

SECTION 4 ........ REPLACEMENT PARTS LIST

1-1

SECTION 1. GENERAL

SERVICING PRECAUTIONS

NOTES REGARDING HANDLING OF THE PICK-UP

1. Notes for transport and storage

1) The pick-up should always be left in its conductive bag until immediately prior to use.

2) The pick-up should never be subjected to external pressure or impact.

2. Repair notes

Storage in conductive bag

1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials.

2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and
impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or
damage to the printed-circuit board.

3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason
the adjustment point and installation screws should absolutely never be touched.

4) Laser beams may damage the eyes!
Absolutely never permit laser beams to enter the eyes!
Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.

NEVER look directly at the laser beam, and don’t allow
contact with fingers or other exposed skin.

5) Cleaning the lens surface
If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used
for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, therefore, a cotton
swab should be used, taking care not to distort lens.

Drop impact

Pressure

Magnet

How to hold the pick-up

Cotton swab

Conductive Sheet

6) Never attempt to disassemble the pick-up.
Spring has excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab.
(Do not use any other liquid cleaners, because they will damage the lens.) Take care not to use too much
of this alcohol on the swab, and do not allow the alcohol to get inside the pick-up.

1-2

Pressure

NOTES REGARDING COMPACT DISC PLAYER REPAIRS

1. Preparations

1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These components
are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components
can be damaged, and for that reason components should be handled with care.

2) The pick-up is composed of many optical components and other high-precision components. Care must be
taken, therefore, to avoid repair or storage where the temperature or humidity is high, where strong magnet­ism is present, or where there is excessive dust.

2. Notes for repair

1) Before replacing a component part, first disconnect the power supply lead wire from the unit

2) All equipment, measuring instruments and tools must be grounded.

3) The workbench should be covered with a conductive sheet and grounded.
When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag. (This is
because there is the possibility of damage by static electricity.)

4) To prevent AC leakage, the metal part of the soldering iron should be grounded.

5) Workers should be grounded by an armband (1 MΩ)

6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent stat­ic electricity changes in the clothing to escape from the armband.

7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin.

Armband

Resistor
(1 MΩ)

Resistor
(1 MΩ)

Conductive
Sheet

1-3

ESD PRECAUTIONS

Electrostatically Sensitive Devices (ESD)

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated
circuits and some field-effect transistors and semiconductor chip components. The following techniques should
be used to help reduce the incidence of component damage caused by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device, which should be removed for potential shock reasons
prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface
such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can

generate electrical charges sufficient to damage ESD devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.

6. Do not remove a replacement ESD device from its protective package until immediately before you are
ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).

7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.

CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER

SAFETY PRECAUTIONS.

8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity sufficient to damage an ESD device).

CAUTION. GRAPHIC SYMBOLS

THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.

THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.

1-4

SERVICE INFORMATION FOR EEPROM

POWER ON

DVD LOGO status

(N0 disc status)

Remote control

pause keyÖ1Ö4Ö7Ö2 in order

Press number 0~9, press character

A~F (1~6 for a while)

Use arrow key (▲/▼/◀/▶) to

move to appropriate position and

make changes

Press pause key once

DETECT NEW EEPROM
(OPTION EDIT SCREEN)

NAME

OPT 1
OPT 2
OPT 3
OPT 4
OPT 5
OPT 6
OPT 7
OPT 8
OPT 9
OPT A

HEX

A5
06
85
B4
00
08
91
01
80
00

Change will be applied
when power OFFÖON

1-5

HOW TO UPDATE AUDIO MICOM & DVD PROGRAMS

1. How to update AUDIO MICOM program.

[Update using CD]

1. Change the filename to download as “MDS715_(Version).HEX”. Only upper cases are permitted.

ex) MDS715 : “MDS715_0709081.HEX”

2. Copy the file to the root folder of a CD and burn it.

3. Insert the CD to the SET, and move to the DVD function.

Then the upgrade process will be started with the upgrade information.

4. If the upgrade process is complete, the set will be rebooted with “Complete” message.

[Update using USB]

1. Change the filename to download as “MDS715_(Version).HEX”. Only upper cases are permitted.

ex) MDS715 : “MDS715_0709081.HEX”

2. Copy the file to the root folder of USB storage.

3. After Home-menu is displayed on Screen of SET, Put the USB into the SET.

Then the upgrade process will be started with the upgrade information.

4. If the upgrade process is complete, the set will be rebooted with “Complete” message.

2. How to update DVD program.

[Update using CD]

1. Copy DVD program(ex: LG_MDS715LD1_Version.Rom) to Root folder of CD, and burn it.

ex) P:LG_MDS715LD1_0911180.Rom

2. Insert the CD to the SET, then after a while the CD tray will be opened with upgrade information on

the screen.

3. Remove the CD, and press “PLAY” key in remote controller.

4. Remove and reconnect the power cable when it changes to logo screen from upgrade information.

Then the upgrade process is completed.

[Update using USB]

1. Copy DVD program(ex: LG_MDS715LD1_Version.Rom) to Root folder of the formatted USB and burn it.

ex) P:\LG_MDS715LD1_0911180.Rom

2. After Home-menu is displayed on Screen of SET, Put the USB into the SET.

Then the upgrade process will be started with the upgrade information.

3. Remove the USB, press "PLAY" key of the remote controller.

4. Remove and reconnect the power cable when it changes to logo screen from upgrade information.

Then the upgrade process is completed.

1-6

SPECIFICATIONS

• GENERAL

Power supply 110~240 V, 50/60 Hz

Power consumption Refer to main label

Dimensions (W x H x D) 273 x 333 x 339 mm without foot

Net Weight (Approx.) 5.7 kg

Operating temperature 41 °F to 95 °F (5 °C to 35 °C)

Operating humidity 5 % to 90 %

Bus Power supply (USB) DC 5V 500mA

• INPUTS/ OUTPUTS

VIDEO OUT 1.0 V (p-p), 75 Ω, sync negative, RCA jack x 1

COMPONENT VIDEO OUT (Y) 1.0 V (p-p), 75 Ω, sync negative, RCA jack x 1,

(Pb)/(Pr) 0.7 V (p-p), 75 Ω, RCA jack x 2

ANALOG AUDIO IN 0.6 Vrms, 47 kΩ, RCA jack (L, R) x 1

PORT. IN 0.5 Vrms (3.5 mm stereo jack)

• TUNER

FM Tuning Range 87.5 to 108.0 MHz or 87.50 to 108.00 MHz

AM Tuning Range 522 to 1 620 kHz, 520 to 1 710 kHz or 522 to 1 710 kHz

• AMPLIFIER

Stereo mode 150 W + 150 W (4 Ω at 1 kHz)

Surround mode

Front 150 W + 150 W (4 Ω at 1 kHz)

Center 70 W (6 Ω at 1 kHz)

Surround 70 W + 70 W (6 Ω at 1 kHz)

Subwoofer 200 W (3 Ω at 60 Hz)

1-7

• SPEAKERS
Front speaker (MDS505V)

rekaeps 2 yaW 2 epyT

4 ecnadepmI Ω

Rated Input Power 150 W

W 003 rewop tupnI .xaM

Net Dimensions(W x H x D) 240 x 387 x 336 mm

gk 5 thgieW teN

Passive Subwoofer (MDS505W)

rekaeps 1 yaW 1 epyT

3 ecnadepmI Ω

Rated Input Power 200 W

W 004 rewop tupnI .xaM

Net Dimensions(W x H x D) 261 x 331 x 409 mm

gk 5.6 thgieW teN

1-8

SECTION 2

CABINET & MAIN CHASSIS

CONTENTS

EXPLODED VIEWS..................................................................................................................................... 2-3

1. CABINET AND MAIN FRAME SECTION (MDT505) ................................................................................ 2-3

2. TAPE DECK MECHANISM SECTION ...................................................................................................... 2-5

3. DVD DECK MECHANISM SECTION (DVM-H1723) ................................................................................ 2-7

4. SPEAKER SECTION .............................................................................................................................. 2-11

5. PACKING ACCESSORY SECTION .......................................................................................................2-13

2-1

MEMO

2-2

EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION (MDT505)

272

iPod

464

A45

251

260

259

254

255

256

261

257

252

262

A42

263L

464

261

464

258

250

270L

FRONT

271

464

269

464

464

265

264

J

E

270R

CABLE1

263R

A43

USB

P

A26

A26

A

276

A26

274

464

B

463

A

B

463

O

464

MAIN

C

D

F

464

463

273

E

G

H

P

I

275

A46

J

464

279

455

VOLUME

253

CABLE2

464

A00

278

CABLE3

SMPS

N

463

464

451

A44

277

L

L

C

D

464

F

A47

464

O

464

CABLE4

464

G

I

H

268

N

300

464

CABLE5

M

M

267A

267A

464

266

464

464

267

267

2-3 2-4

2. TAPE DECK MECHANISM SECTION (A/R & A/S : RIGHT A/R DECK)

A00

009

003

001

007

037

015

006

017

020

019

022

018

A01

023

025

011

A02

009

2-5 2-6

3. DVD DECK MECHANISM SECTION (DVM-H1723)

151

A26

153A

159

156

153

177

167

172

166

170

162

163

175

164

181

165

155

173

180

169A

169B

169C

430

012

A02

012

010

137

A01

430

012

430

035

2-7 2-8

MEMOMEMO

2-9 2-10

4. SPEAKER SECTION

4-1. FRONT SPEAKER (MDS505V)

A60

2-11

4-2. PASSIVE SUBWOOFER (MDS505W)

A90

2-12

5. PACKING ACCESSORY SECTION

808 Battery

811 RCA Cable, 1 Pin(Black)

900 Remote Control

803 Packing, Casing

824 AM Loop Antenna

825 FM Wire Antenna

801 Owner’s Manual

804 Bag

802 Box

2-13

MEMO

2-14

SECTION 3

ELECTRICAL

CONTENTS

ELECTRICAL TROUBLESHOOTING GUIDE .................................................................................... 3-2

DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING ................................ 3-16

WIRING DIAGRAM ................................................................................................................................... 3-29

BLOCK DIAGRAM .................................................................................................................................... 3-31

CIRCUIT DIAGRAMS ............................................................................................................................... 3-33

1. SMPS - POWER CIRCUIT DIAGRAM ................................................................................................. 3-33

2. MAIN - MICOM CIRCUIT DIAGRAM .................................................................................................... 3-35

3. MAIN - PWM CIRCUIT DIAGRAM ....................................................................................................... 3-37

4. MAIN - AMP CIRCUIT DIAGRAM ........................................................................................................ 3-39

5. MAIN - DECK CIRCUIT DIAGRAM ...................................................................................................... 3-41

6. MAIN - MPEG CIRCUIT DIAGRAM ..................................................................................................... 3-43

7. MAIN - SERVO CIRCUIT DIAGRAM ................................................................................................... 3-45

8. MAIN - I/O CIRCUIT DIAGRAM ........................................................................................................... 3-47

9. VFD CIRCUIT DIAGRAM ..................................................................................................................... 3-49

10. MIC & USB CIRCUIT DIAGRAM .......................................................................................................... 3-51

11. VOLUME CIRCUIT DIAGRAM ............................................................................................................. 3-53

12. IPOD CIRCUIT DIAGRAM (OPTIONAL PART) ................................................................................... 3-55

13. KARAOKE CIRCUIT DIAGRAM (OPTIONAL PART) ........................................................................... 3-57

CIRCUIT VOLTAGE CHART ................................................................................................................. 3-59

PRINTED CIRCUIT BOARD DIAGRAMS ......................................................................................... 3-61

1. MAIN P.C.BOARD ................................................................................................................................ 3-61

2. SMPS P.C.BOARD ............................................................................................................................... 3-65

3. FRONT(VFD / USB & MIC / VOLUME) P.C.BOARD ........................................................................... 3-67

4. IPOD P.C.BOARD (OPTIONAL PART) ................................................................................................ 3-69

5. KARAOKE P.C.BOARD (OPTIONAL PART) ....................................................................................... 3-69

3-1

ELECTRICAL TROUBLESHOOTING GUIDE

1. SMPS BOARD

No power.

Check the AC

line pattern.

YES

Check fuse F901.

YES

Check C978

voltage (3.9 V).

YES

Check C963

voltage (5.6 V).

YES

NO

NO

NO

NO

Connect the open line.

Replace F901.

Check BD901 “+”

to “

-

” Pin impedance .

Check 3.7 V lines short.

Replace PC972, IC902’s components.

Check SMPS second part lines short.

Check MAIN or AMP board short.

Low impedance:

Replace IC901, BD901.

Check IC901

Vcc voltage (10 V ~ 30 V).

YES

Replace SMPS board.

NO

Replace PC951, PC972, IC901.

Check around IC901’s components

(Short, Open).

3-2

ELECTRICAL TROUBLESHOOTING GUIDE

No sound.

Check IC961

Vcc voltage(34 V ~ 43 V).

YES

Check C955 voltage

(25 V or 36 V).

YES

Replace IC961, IC901 or

SMPS board.

NO

NO

Check no power list, AC input voltage.

Check AMP module short.

Replace PC951, IC901.

3-3

ELECTRICAL TROUBLESHOOTING GUIDE

2. FRONT BOARD

Power on.

“WELCOME”

Display

on VFD ok?

YES

Volume LED

(LD301~LD315)

turn on?

NO

NO

PN301 cable

connection ok?

YES

PN301 Pin1,2,3,6

power ok?

YES

PN301

Pin7, 8, 9, 10 data signal

ok?

YES

IC301

check ok?

YES

Digitron (DIG301) ok?

PN301 Pin21

+12 V ok?

NO

NO

NO

NO

NO

NO

Check 36p FFC cable.

Check SMPS board.

Check MAIN board.

Replace IC301.

Replace DIG301.

Check SMPS board.

YES

When you turn

the volume knob, count

is change?

YES

FRONT board ok.

NO

YES

Check

PN301 Pin11,13,29~36

data signal.

YES

Replace LED (LD301~LD315).

PN301 Pin22, 26

signal ok?

YES

Check MAIN board.

3-4

NO

NO

Check Main board.

Check 5p FFC cable.

ELECTRICAL TROUBLESHOOTING GUIDE

3. NO AUDIO CHECK

CD/DVD Disc

or USB play.

IC602 Pin4, 5,

6, 7, 8 I2S input

signal ok?

YES

IC602 I2S

output signal

ok?

YES

A

PORTABLE function.

NO

NO

Check IC500.

Check IC602.

AUX function.

IC200

Pin7,8 audio

L/R ok?

YES

B

HEADPHONE output.

NO

Check JK201.

IC200

Pin21, 22 audio

L/R ok?

YES

B

NO

Check JK301.

IC301

Pin 1, Pin 7

audio signal

ok?

YES

Front Board

CN301 Pin1,3 audio

signal ok?

YES

Check Front Board stage
and JK301.

NO

NO

Check IC301.

Check CN301 and
Connection.

3-5

ELECTRICAL TROUBLESHOOTING GUIDE

IPOD function.

YES

IPOD B/D

CN201 Pin27,

28 audio L/R

ok?

YES

IPOD B/D

CN202 Pin13, 15

ok?

YES

MAIN B/D

PN201 Pin13, 15

ok?

YES

IC200

Pin26, 27 audio

signal ok?

YES

B

NO

NO

NO

NO

Check IPOD

connection or CN201.

Check IPOD Board.

Check 15p Harness

and connection.

Check IC251.

TUNER Function.

Pin23,24 audio

L/R ok?

B

A

Pin42, 43, 44 I2S

clock ok?

Pin41 I2S output

signal ok?

Pin4~8 I2S
input signal

I2S output signal

IC701 audio

output signal

Check AMP IC output

stage and JK701(JK702).

IC200

IC200

IC200

IC602,

ok?

IC602

ok?

ok?

YES

YES

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

NO

Check Tuner (TU345)

and Antenna

connection.

Check IC500 and

X500.

Check IC200.

Check IC500.

Check IC602.

Check IC701.

3-6

ELECTRICAL TROUBLESHOOTING GUIDE

4. NO VIDEO CHECK

COMPONENT video out.

IC201 Pin2, 3, 4
video signal ok?

IC201 Pin11, 12, 13

video signal ok?

Check JK201.

CVBS video out .

IC252 Pin3

video signal ok?

YES

YES

NO

NO

NO

Check IC500.

Check IC500.

Check IC201.

YES

IC252 Pin4

video signal ok?

YES

IC201 Pin14

video signal ok?

YES

Check JK201.

NO

NO

IC252

Pin6 LOW

signal?

YES

Check IC252.

Check IC201.

3-7

NO

Check Micom (IC101).

ELECTRICAL TROUBLESHOOTING GUIDE

CVBS video out

(IPOD video).

IPOD B/D

CN201 Pin23 video

signal ok?

YES

IPOD B/D

CN202 Pin10 ok?

YES

MAIN B/D

IC250 Pin4 ok?

YES

IC252 Pin1

video signal ok?

YES

IC252 Pin4

video signal ok?

NO

NO

NO

NO

NO

Check IPOD connection

or CN201.

Check IPOD Board.

Check 15p Harness cable

and connection.

Check IC250.

IC252

Pin6 HIGH

signal?

NO

Check Micom (IC101).

YES

IC201 Pin14

video signal ok?

YES

Check JK201.

NO

YES

Check IC252.

Check IC201.

3-8

5. SYSTEM OPERATION FLOW

POWER ON.

1. Initializes SERVO, DSP & RISC registers.

2. Write RISC code to SDRAM.

3. Reset RISC.

Show LOGO.

YES

Tray closed?

NO

Tray close to closed position.

SLED at inner

side?

NO

SLED moves to inner position.

1. Judge whether have disc and disc type.

2. Jump to related disc reading procedure.

Recieve

OPEN/ CLOSE

Key?

YES

YES

NO

NO

1. Execute Pressed Key & IR Key.

2. System operation routine loop.

1. Stop Playback & Open Tray.

2. Display tray open message & LOGO.

YES

Receive

CLOSE Key?

YES

3-9

6. TEST & DEBUG FLOW

TEST.

YES

Check the

AC voltage Power PCBA (110 V

or 220 V).

YES

Switch on the Power PCBA.

YES

Are the

DC Voltage outputs OK? (from the SMPS).

YES

Are 3.7, 5.6, 12 and

28 V(36V) DC outputs normal on

Main PCBA?

YES

Update

FLASH successfully?

YES

NO

NO

NO

NO

Check the POWER PART.

Check the POWER PART.

Check the regulators or diode.

1. Check 27 MHz system clock.

2. Check system reset circuit.

3. Check FLASH R/W enable signal PRD,
RWR.

4. Check FLASH Memory related circuit.

NO

A

Replace FLASH.

3-10

A

YES

Power On.

YES

Show LOGO?

YES

Does Tray

move inside when it

is not at closed

position?

NO

NO

Flash

Memory operates

properly?

YES

SDRAM

works properly?

YES

MT1389SE/GH
VIDEO outputs

properly?

YES

Check AV cable

connection to TV set.

Normal

OPEN_SW,

CLOSE_SW

signal?

NO

NO

NO

NO

Check connection lines between
FLASH & MT1389SE/GH and
the FLASH access time
whether is suitable or not.

Check connection lines
between SDRAM(IC503) &
MT1389SE/GH and the
SDRAM is damaged.

Check the related circuit of
MT1389SE/GH IC500 Pin139,
143, 145, 146.

Check the load OPEN &
CLOSE switch.

B

YES

YES

Normal

TROPEN & TRCLOSE

signal?

YES

Normal

LOAD+ & LOAD-

signal?

YES

Check FFC cable connection
between main PCBA and
loader. (MECHA)

3-11

NO

NO

Check the Tray control IO Pin
on MT1389SE/GH and IC401.

Check the Tray control MOTOR &
SERVO circuit IC400.

B

YES

Does

the SLED move to inner

side when it is at outer

position?

YES

Do not put in disc

and close tray.

NO

Motor

Driver M_STBY

Pin is high?

YES

Motor

Driver SLD

Pin is High?

YES

SLED+ and

SLED- output

properly?

YES

Check the cable connection

with MECHA.

NO

NO

NO

Check the connection line of
M_STBY.

Check the related circuit of
SLD.

Check the amp circuit on motor
driver.

Optical Lens

has movements for

searching Focus?

YES

C

NO

Proper

Focus outputs

to motor driver?

YES

Proper F+ & F-

outputs?

YES

Check cable connection with

pick-up head.

3-12

NO

NO

Check Focus connection on

MT1389SE/GH

Check the amp circuit on motor

and motor driver.

driver.

C

YES

Laser

turns on when

reading disc?

YES

Put disc in?

YES

Disc ID is correct?

NO

NO

NO

DVDLD or

CDLD output

property?

YES

Collector

voltage of power transistor

is OK?(Q400, Q401)

YES

Check cable connection

between transistor output and

pick-up head(23p FFC).

Laser off.

Proper

RF signal on

MT1389SE/GH.

NO

NO

NO

Check the laser power circuit
on MT1389SE/GH and
connecting to power transistor.
(Q400, Q401).

Check the related circuit on

laser power transistor.

Check the related circuit on

MT1389SE/GH RF signal.

YES

Does sPindle rotate?

YES

D

NO

YES

Check the RF connection

between S3053 and MT1389SE/GH.

Proper

SPinDLE signal on

MT1389SE/GH.

YES

SPNP

& SPNN output

properly?

YES

Check the cable connection

between sPindle and main

PCB(15p FFC).

3-13

NO

NO

Check the SPinDLE related

circuit on MT1389SE/GH.

Check the sPindle control amp

circuit of motor driver.

D

YES

Focus on ok?

YES

Track On OK?

YES

NO

NO

Proper

signals on A, B, C,

D of MT1389SE/GH.

YES

Proper

CD_DVDCT signal on

MT1389SE/GH.

YES

Check CD_DVDCT connection

between S3053 and

MT1389SE/GH.

Proper

CD_DVDCT signal on

MT1389SE/GH.

YES

Proper

TRACK signal

on MT1389SE/GH.

NO

NO

NO

NO

Check connections between

MT1389SE/GH and pick-up head.

Check the related circuit on

MT1389SE/GH CD_DVDCT.

Check the related circuit on

MT1389SE/GH.

Check the TRACK connection

on MT1389SE/GH and motor driver.

Disc Playback?

YES

E

NO

YES

T+ & T- output

properly?

YES

Check cable connection

on pick-up head.

Check RF signal waveform.

3-14

NO

Check the tracking control amp

circuit on motor driver.

E

YES

Normal Audio

output when disc

playback?

YES

TEST END.

NO

IC602(PWM IC)

received correct data

stream?

YES

Normal

PWM IC out?(IC602).

YES

Check AMP IC

(IC701, 702, 703).

NO

NO

Check connection between
IC500 BCK, LRCK, ADATA0,
ADATA1, ADATA2(Pin157,
158, 160, 161, 162).

Check the related circuit of

PWM IC

3-15

DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING

4

1

2

3

1. SYSTEM 27 MHz CLOCK,RESET,FLASH R/W SIGNAL

1)

MT1389SE/GH

2)

MT1389SE/GH

Power Cord in

main clock is at 27 MHz(X500)

1

FIG 1-1

reset is high active.

P_CTL

DVD_RST

RESET_IN

2

3

4

FIG 1-2

3-16

3) Flash R/W enable signal during download(Downloading)

5

6

7

5

SF_DI

SF_DO

2. SDRAM CLOCK

1)

MT1389SE/GH

DCLK = 93 MHz, Vp-p = 2.2, Vmax = 2.7 V

main clock is at 27 MHz(X500)

6

FIG 1-3

SDCLK

7

FIG 2-1

3-17

3. VIDEO PART-1 (100% FULL COLOR-BAR)

8 9

11

8

10

9

10

CVBS_I Y

11

Pb Pr

3-18

4. VIDEO PART-2 (100% FULL COLOR-BAR)

12 13

14 15

12

14

13

CVBS COMP_Y

15

COMP_Pb COMP_Pr

3-19

5. SERVO OPEN/CLOSE SIGNAL

17

16

19 18

1) Tray open/close waveform

OPENSW

CLOSESW

OPEN

CLOSE

FIG 5-1

3) Tray open waveform

OPENSW

2) Tray close waveform

OPENSW

16

CLOSESW

17

OPEN

18

19

16

CLOSE

FIG 5-2

16

17

18

19

CLOSESW

OPEN

CLOSE

17

18

19

FIG 5-3

3-20

20

22

23

21

6. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION)

SLD

M-STBY

SL+

SL-

FIG 6-1

20

21

22

23

3-21

7. LENS CONTROL RELATED SIGNAL(NO DISC CONDITION)

24

26

25

28

27

29

FOD

F+

F-

24

25

26

FIG 7-1

8. LASER POWER CONTROL RELATED SIGNAL(NO DISC CONDITION)

MDI1

DVDLD

CDLD

FIG 8-1

27

28

29

3-22

9. DISC TYPE JUDGEMENT WAVEFORMS

30

32

31

F+

PU_DET

RF

FIG 9-1 (DVD)

F+

PU_DET

30

31

32

31 : This signal can see using special debug program

30

31

RF

32

FIG 9-2 (DVD)

3-23

F+

35

34

33

33

PU_DET

RF

F+

PU_DET

RF

34

35

FIG 9-3 (CD)

34 : This signal can see using special debug program

33

34

35

FIG 9-4 (CD)

3-24

10. FOCUS ON WAVEFORMS

37

39

38

36

36 : This signal can see using special debug program

PU_DET

FOD

F+

F-

PU_DET

FOD

F+

F-

36

37

38

39

FIG 10-1 (DVD)

36

37

38

39

FIG 10-2 (CD)

3-25

40

42 41

11. SPINDLE CONTROL WAVEFORMS (NO DISC CONDITION)

FIG 11-1

SPinD

40

SP-

41

SP+

42

3-26

46 45

44

12. TRACKING CONTROL RELATED SIGNAL(System checking)

43

43 : This signal can see using special debug program

PU_DET

PU_DET

43

TRO

TRO

44

T-

T+

T-

T+

PU_DET

TRO

45

46

FIG 12-1(DVD)

PU_DET

43

TRO

44

T-

45

T+

46

FIG 12-2(CD)

3-27

MEMO

3-28

MIC/USB

PCB

JOG PCB

WIRING DIAGRAM

TUNER

MODULE

DC FAN

AUX

JACK

23P

CN400

2P

23P

15P

CN401

3 CD CHANGER MD

P7708

2P

5.1 CH SPK TERMINAL

SMPS PCB

MAIN

PCB

8P

PN102

CN301

8P

P1001

PN301

36P

9P

P8502

6P

DECK

MECHANISM

5P

36P

CN302

5P

8P

P8501

PN304

CN200

4P

15P

PN201

15P 10P

CN102

2P

CN502

FRONT PCB

CN501

CN101

7P

PN101

IPOD PCB

CN202

CN952

CN951

3-29 3-30

2P

KARAOKE

PCB

BLOCK DIAGRAMS

DECK S/W

PLAY/REC L/R

Deck

SOL/MOTOR

REC_BIAS

EXP_DATA,CLK

REC/PB_MUTE

HA12237F

Cassette

Deck ASP

TAPE

S-24CS16A01

REC_L/R

EEPROM

REMOCON

MODULE

HALL,LEAF

MCLK,BCLK

LRCLK,DATA

EEPROM

DATA,CLK

9.8304 MHz

LC87F5N

C8A

AUDIO

MICOM

(3.3V)

SPI(4P)DVD_RST

KIA7027

RESET

KIA7027

PWR_SENS

DSP_BSY
DSP_IBO

PWM_RST
DATA,CLK

PWM/DSP_CLK

PWM/DSP_DATA

PS9850

DSP/
PWM

Modulat

AMP_SD
AMP_OTW

AMP_PDN

Power Amp

FAN_AD

FAN

FAN_CTRL

FL

FR

S/W

TAS5614

RR

C/T

RL

Tuner

Aux-IN

Portable

IPOD

USB

MIC

H/PHONE

Composite

Component

D+, D-

IPOD VIDEO

/ CVBS

R/G/B

PR/Y/PB

NJM2505

VIDEO NOISE

ISOLATION

S4308

OP AMP

MC4580

OP AMP

THS7314

VIDIO FUNC

CS5346

ADC

H/P_ L/R

UART

NLASB

3157

DFT2G

VIDEO SW

LRCLK, BCLK

MCLK

5346_DATA

MIC L/R

IPOD VIDEO

CVBS

Y/G

Pb/B

Pr/R

27 MHz

MTK1389GH

MPEG

DATA

CP2.0

IPOD

RST,CLK

HY57V

64614

20HG

SDRAM

DMA[0-10]

DB[0-15]

SCL

W25Q

16BY

FLASH

SDA

KSC24

1021CS

EEPROM

SCL

SDA

6302_DO

6302_DI

OPEN/CLOSE

FOCUS/SLED

SPINDLE/TRACKING

6315_CLK
6315_STB

PT6302

VFD

DRIVER

GR[1-12]
SG[1-16]

VFD

MD_DVD, MD_CD
LD_DVD, LD_CD
VR_DVD, VR_CD

Motor
Driver

S3053

/S8082

A, B, C, D, E, F, RF

F+/-, T+/-

SLED+/­SPINDLE+/­LOAD+/­OPEN/CLOSE

PICK-UP

Motor

MDS715:5.1ch

MDT505:2.1ch
MDD305 : 2ch

TJ3965D

3.3V LDO
TO

PWM/TUNE

R

KIA78R05

5V

TO USB

LM39102

5V LDO

TO IPOD

LM39102

5V LDO

TO MPEG

MO8706EN
DC/DC3.3V

TO MPEG

3-31 3-32

CIRCUIT DIAGRAMS

1. SMPS - POWER CIRCUIT DIAGRAM

12

11

10

9

8

IMPORTANT SAFETY NOTICE

WHEN SERVICING THIS CHASSIS, UNDER NO
CIRCUMSTANCES SHOULD THE ORIGINAL DESIGN BE
MODIFIED OR ALTERED WITHOUT PERMISSION
FROM THE LG CORPORATION. ALL COMPONENTS
SHOULD BE REPLACED ONLY WITH TYPES IDENTICAL
TO THOSE IN THE ORIGINAL CIRCUIT. SPECIAL

COMPONENTS ARE SHADED ON THE SCHEMATIC
FOR EASY IDENTIFICATION.
THIS CIRCUIT DIAGRAM MAY OCCASIONALLY DIFFER
FROM THE ACTUAL CIRCUIT USED. THIS WAY,
IMPLEMENTATION OF THE LATEST SAFETY AND
PERFORMANCE IMPROVEMENT CHANGES INTO
THE SET IS NOT DELAYED UNTIL THE NEW SERVICE
LITERATURE IS PRINTED.

NOTE :

1. Shaded(

2. Voltages are DC-measured with a digital voltmeter

) parts are critical for safety.

Replace only with specified part number.

during Play mode.

7

6

5

4

3

2

CAUTION:

Danger if fuse is incorrectly replaced.

1

A

Replace only with the type identical to fuse rating

and(or) model name described in main label.

B C D E F G H I J K L M N O P Q R ST

Warning
Parts that are shaded are critical with
respect to risk of fire or electrical shock.

MDS715

EBY60928901 REV 4.1

SMPS

2010. 09. 15

3-33 3-34

2. MAIN - MICOM CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #001 MICOM
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-35 3-36

3. MAIN - PWM CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #002 PWM
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-37 3-38

4. MAIN - AMP CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #003 AMP
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-39 3-40

5. MAIN - DECK CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #004 DECK
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-41 3-42

6. MAIN - MPEG CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #005 MPEG
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-43 3-44

7. MAIN - SERVO CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715
MAIN #006 SERVO
EBY60749301 REV 7.1

A

B C D E F G H I J K L M N O P Q R ST

3-45 3-46

8. MAIN - I/O CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

A

B C D E F G H I J K L M N O P Q R ST

MDS715
MAIN #007 I/O
EBY60749301 REV 7.1

3-47 3-48

9. VFD CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715/MD505/MDD305
VFD(FRONT)
EBY60729301 REV 6.2

A

B C D E F G H I J K L M N O P Q R ST

3-49 3-50

10. MIC & USB CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

A

B C D E F G H I J K L M N O P Q R ST

MDS715/MDT505/MDD305/MCT565
MIC & USB
EBY60729401 REV 6.2

3-51 3-52

11. VOLUME CIRCUIT DIAGRAM

12

11

10

9

8

7

6

5

4

3

2

1

MDS715/MDT505/MDD305
MAIN VR & JOG VOL

A

B C D E F G H I J K L M N O P Q R ST

EBY60729501 REV 2.2

3-53 3-54

12. IPOD CIRCUIT DIAGRAM (OPTIONAL PART)

12

11

10

9

8

7

6

5

4

3

2

1

MDS715/MDT505-IPOD
EBY60729701 REV 5.2

A

B C D E F G H I J K L M N O P Q R ST

3-55 3-56

13. KARAOKE CIRCUIT DIAGRAM (OPTIONAL PART)

12

11

10

9

8

7

6

5

4

3

2

1

A

B C D E F G H I J K L M N O P Q R ST

MDS715/MDT505/MDD305
NO-KEY
EBY60729601 REV 4.1

3-57 3-58

CIRCUIT VOLTAGE CHART

NO. IC Symbol NAME/TYPE SPEC. VOLTAGE

1

2

3

4

5

6

IC101

MICOM

IC200

ADC IC

IC400

MOTOR

DRIVE

IC503

SDRAM

IC504

FLASH

IC602

PWM

LC87F5NC8A

VDD: 14,40,55,89

CS5346-CQZR

LVC:5

VLS:36

VD:46
VA:14

GND: 13, 31, 32

S3053

VCC:8,19

EM638165TS-6G

VDD: 1,3,9,14,27,43,49

MX25L1605DM21-12G

VDD:8

PS9850

VDD : 1,16,21,24,29,32,35,40,

43,48,57,59,60,61,64

VDD: +3.0 ~ +5.5V

VLS,VD,VLC:

1.71~5.25V
VA:3.1~5.25V

VCC: +4.3 ~ 13.2V VCC:+4.98V

VDD: +3 ~ +3.6V VCC: +3.33V

VDD: +2.7 ~ +3.6V VDD: +3.31V

IOVDD : +2.97V ~ +3.63V IOVDD : +3.28V

VDD 14 PIN: +3.28V

40,55,89 PIN : +3.28V

VLS,VD,VLC:3.35V

VA:5.2V

NO. LOCA. NO. Capacity Spec.(V)

1 BD901 600 127.3 373.3

2 C901 150 uF 450 127.3 373.3

3 C902 150 uF 450 127.3 373.3

4 C909 4.7 uF 50 19.6 19.6

5 C910 22 uF 50 22.0 22.0

6 C913 22 uF 50 22.2 22.2

7 C952 470 uF 50 43.1 43.1

8 C955 470 uF 50 43.1 43.1

9 C961 470 uF 50 43.1 43.1

10 C963 1000 uF 10 7.32 7.32

11 C965 47 uF 50 38.6 38.6

12 C966 1000 uF 25 12.6 12.6

13 C967 100 uF 10 4.96 4.96

14 C971 1000 uF 10 3.92 3.92

15 C978 220 uF 10 3.92 3.92

16 C979 220 uF 10 5.8 5.8

17 D901 600 251.0 474.0

18 D906 400 44.0 86.0

19 D907 400 77.2 178.0

20 D910 400 84.4 195.0

21 D951 200 95.2 181.0

22 D961 40 44.4 44.4

23 D962 60 57.6 57.6

24 D963 400 404.0 404.0

25 D964 400 60.0 60.0

26 D971 60 14.6 34.4

27 IC901 32 19 19

28 IC902 32 20.8 20.8

29 IC961 43 42.2 42.2

30 Q901 600 301.0 540.0

100V - 10% 240V/50Hz+10%

Voltage(V) Voltage(V)

3-59 3-60

PRINTED CIRCUIT BOARD DIAGRAMS

1. MAIN P.C.BOARD

(TOP VIEW)

3-61 3-62

MAIN P.C.BOARD

(BOTTOM VIEW)

3-63 3-64

2. SMPS P.C.BOARD

MDS715

EAX35194121 REV 4.2

2010. 06. 11

NOTE) Warning

Parts that are critical with respect to risk
of fire or electrical shock.

3-65 3-66

3. FRONT(VFD / USB & MIC / VOLUME) P.C.BOARD

3-67 3-68

4. IPOD P.C.BOARD (OPTIONAL PART)

(TOP VIEW) (BOTTOM VIEW)

5. KARAOKE P.C.BOARD (OPTIONAL PART)

3-69 3-70

MEMO MEMO

3-71 3-72