LG MBD62I, MBS62V Schematic

MINI HOME THEATER SYSTEM

SERVICE MANUAL

MODEL: MBD62I, MBS62V

CAUTION

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

MODEL: MBD62I, MBS62V

SERVICE MANUAL

P/NO : AFN35036930

SEPTEMBER, 2007

Website http://biz.lgservice.com

Internal Use Only

CONTENTS

SECTION 1 SUMMARY

SERVICING PRECAUTIONS......................................1-2

• NOTES REGARDING HANDLING OF THE PICK-UP

•

NOTES REGARDING COMPACTDISC PLAYER REPAIRS

ESD PRECAUTIONS...................................................1-4

SPECIFICA TIONS........................................................1-5

SECTION 2 EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION..............2-1

2. DECK MECHANISM SECTION (DP-12A).............2-3

3. SPEAKER SECTION (MBS62V) ............................2-5

4. PACKING ACCESSORY SECTION .......................2-6

SECTION 3 ELECTRICAL

ELECTRICAL TROUBLESHOOTING

GUIDE OF AUDIO PART.............................................3-1

1. MICOM PART CHECK I....................................3-1

2. MICOM PART CHECK II...................................3-2

3. IC103 KS4CD21CS CHECK.............................3-3

4. FLD DISPLAY CHECK......................................3-4

5. PWM MODULATION PART..............................3-5

6. POWER AMPPART CHECK............................3-6

7. PORTABLE FUNCTION....................................3-7

8. TV-AUDIO FUNCTION......................................3-8

9. TUNER FUNCTION CHECK ............................3-9

10. SMPS POWER TROUBLESHOOTING.........3-10

11. BLUETOOH PART (OPTIONAL PART)..........3-13

12. IPOD PART (OPTIONAL PART).....................3-14

ELECTRICAL TROUBLESHOOTING

GUIDE OF DVD PART...............................................3-15

1. POWER CHECK GUIDE.................................3-15

2. TEST & DEBUG FLOW...................................3-16

3. USB PART........................................................3-21

WAVEFORMS.............................................................3-22

1. WHEN POWER ON, RESET & DATA

ETC WAVEFORM............................................3-22

2. OPEN / CLOSE WAVEFORM AT

POWER ON......................................................3-23

3. STARTING ACTION WAVEFORM

IN MD DEVICE ................................................3-23

4. FOCUS WAVEFORM......................................3-24

5. AT POWER ON, SPINDLE SIGNALAT

MD DECK .........................................................3-25

6. A T FIRST ACTION, FOCUS

SIGNALA, B, C, D............................................3-25

7. TRACKING SIGNAL........................................3-26

8. RF WAVEFORM ..............................................3-26

9. DISK TYPE JUGEMENT WAVEFORM..........3-27

INTERNAL BLOCK DIAGRAM OF ICs...................3-28

1. AK5358..............................................................3-28

2. EM639165 ........................................................3-30

3. ES29LV160E ....................................................3-32

4. HT1000 .............................................................3-34

5. IP9009...............................................................3-37

6. KS24L161.........................................................3-38

7. MC4580 ............................................................3-39

8. PS9829B...........................................................3-40

9. PT6324..............................................................3-41

10. STR-A6252.......................................................3-44

11. µPD78F0546R (R)............................................3-45

WIRING DIAGRAM....................................................3-49

BLOCK DIAGRAMS..................................................3-51

1. SMPS BLOCK DIAGRAM...............................3-51

2. MAIN & FRONT BLOCK DIAGRAM ..............3-53

SCHEMATIC DIAGRAMS .........................................3-55

1. SMPS SCHEMATIC DIAGRAM......................3-55

2. MAIN, INTERFACE & PWM

SCHEMATIC DIAGRAM..................................3-57

3. MPEG SCHEMATIC DIAGRAM.....................3-59

4. SERVO SCHEMATIC DIAGRAM...................3-61

5. INTERFACE SCHEMATIC DIAGRAM...........3-63

6. FRONT SCHEMATIC DIAGRAM ..................3-65

7. FRONT MIC SCHEMATIC DIAGRAM...........3-67

8.

IPOD-1 SCHEMATIC DIAGRAM (OPTION)

9.

IPOD-2 SCHEMATIC DIAGRAM (OPTION) 2 CHANNELAMP SCHEMATIC DIAGRAM

10.

11. BLUTHOOTH MODULE

SCHEMATIC DIAGRAM (OPTION)................3-75

CIRCUIT VOLTAGE CHART.....................................3-77

PRINTED CIRCUIT BOARD DIAGRAMS ...............3-79

1. MAIN P.C.BOARD............................................3-79

2. FRONT P.C.BOARD........................................3-83

3. SMPS P.C.BOARD ..........................................3-85

4. MIC JACK P.C.BOARD ...................................3-87

5. IPOD P.C.BOARD (OPTION)..........................3-87

.....3-69

.....3-71

......3-73

SECTION 4 REPLACEMENT PARTS LIST

........4-1

1-1

LGE Internal Use Only

SECTION 1 SUMMARY

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

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.

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 this.

6) Never attempt to disassemble the pick-up. Spring by 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.

LGE Internal Use Only

1-2

Only for training and service purposes

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 of 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 (1MΩ)

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.

1-3

LGE Internal Use Only

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 know 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 ARROWHEAD 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 INTENED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

LGE Internal Use Only

1-4

Only for training and service purposes

SPECIFICATIONS

• GENERAL

Power supply Refer to the back panel of the unit. Power consumption Refer to the back panel of the unit. Net Weight 3.00kg External dimensions (WxHxD) 300 x 130 x 243mm

• CD/DVD

Laser Semiconductor laser, wavelength 650nm Signal system PAL 625/50, NTSC 525/60 Frequency response (audio) 40Hz to 20kHz Signal-to-noise ratio (audio) More than 75dB (1kHz, NOP -3dB, 20kHz LPF/A-Filter) Dynamic range (audio) More than 75dB Harmonic distortion (audio) 0.5 % (1kHz, at 1W position) (20kHz LPF)

• VIDEO

Video output 1.0V (p-p), 75Ω, negative sync./ RCA jack x 1/ SCART (TO TV) COMPONENT VIDEO OUT (Y) 1.0V (p-p), 75ohms, negative sync, RCA jack x 1

(Pb)/(Pr) 0.7V (p-p), 75ohms, RCA jack x 1

• TUNER

FM Tuning Range 87.5 ~ 108.0MHz or 65 ~ 74MHz, 87.5 ~ 108.0MHz

Intermediate Frequency 10.7MHz Signal to Noise Ratio 60/55dB Frequency Response 50 ~ 10000Hz

AM Tuning Range 522 ~ 1620kHz or 520 ~ 1720kHz

Intermediate Frequency 450kHz Signal to Noise Ratio 30dB Frequency Response 80 ~ 1800Hz

• AMPLIFIER

Output Power 30W + 30W T.H.D 0.5% Frequency Response 40 ~ 20000Hz Signal-to-noise ratio 75dB

• SPEAKERS

Speaker Name MBS62V Type Bass Reflex 2 Way 2 Speaker Impedance 4Ω Frequency Response 60 ~ 20000Hz Sound Pressure Level 82dB/W (1m) Rated Input Power 30W Max. Input Power 60W Net Dimensions (WxHxD) 160 X 308 X 204mm Net Weight (1EA) 2.5kg

Designs and specifications are subject to change without notice.

1-5

LGE Internal Use Only

MEMO

LGE Internal Use Only

1-6

Only for training and service purposes

SECTION 2 EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION

463

461

463

A43

A50

A26

A

C

D

461

E

A47

463

250

463

B

257

CABLE3

463

G

F

G

461

A

H

275

463

E

C

300

256

261

463

A46

B

D

F

461

IPOD

276

CABLE2

258

259

463

272

A44

273

2-1 2-2

463

274

LGE Internal Use Only

2. DECK MECHANISM SECTION (DP-12A)

A26

001

026

A02

017

013

435

015

439

018

015B

015A

014

440

002

003

A01

020

016

LGE Internal Use Only

A03

019

442

012

012A

442

010

2-3 2-4

Only for training and service purposes

3. SPEAKER SECTION (MBS62V)

A70

A70A

755

751

750

753

757

757A

756

752

758

754

759

2-5

LGE Internal Use Only

4. PACKING ACCESSORY SECTION

824

Antenna Loop

Antenna

825

900

Remote control

808

Plug Ass'y, 1Way(BLACK)

811

Instruction Ass'y

801

Battery

803

802

Bag804

Packing

Box

803A

Packing

LGE Internal Use Only

2-6

Only for training and service purposes

SECTION 3 ELECTRICAL

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

1. MICOM PART CHECK I

MICOM part check I

YES

Check P7904

6PIN P-SENS

YES

Check

power of both

terminals of IC101

KIA7042

YES

Check IC100 78KO/KF2

1PIN power

YES

OK OK

NO

Refer to SMPS

Troubleshooting

Check

if IC101 KIA7042

input is over 5V.

YES

Check if output voltage

of IC101 KIA7042 is 4.3V

YES

NO

Check

the related part of

IC101 KIA7042

YES

NO

Replace the

related parts

3-1

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

2. MICOM PART CHECK II

MICOM part check II

YES

Check P7904

5PIN 5.6V

YES

Check power of

both terminals of D101

1SR35

YES

Check

Q101 EMITTER 5V

and COLLECTOR

5V

YES

Check IC103 8PIN IC100

19, 20, 59PIN 5V

NO

NO NO

Refer to SMPS

Troubleshooting

Check D101 1SR35

output is working on 5V

YES

Check the

related part

YES

OK

Check Q102

BASE PIN 0.6V

HIGH

YES

Check Q102 COLLECTOR

NO

Replace the related parts

Check output power of IC101 KIA7042 is

over 4.3V.

YES

Check the

related part.

NO

Replace the

related parts

YES

Check the working condition

X101: 32.768kHz

X100: 9.8304MHz

YES

OK

LGE Internal Use Only

YES

Check the

related part.

YES

OK

3-2

NO

YES

OK

Replace the related parts

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

3. IC103 KS4CD21CS CHECK

Check IC100 78KOKF2

22, 24PIN

YES

22 PIN DATA

24 PIN CLK

YES

OK

Check MICOM

power 5V

YES

Check the

related part

YES

OK

NONO

NO

Refer to MICOM

Troubleshooting

Replace the related parts

3-3

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

4. FLD DISPLAY CHECK

FLD display check

YES

Check P7904

1,2,3 power.

YES

F1+,F2- both

terminals: over 3.7V

Check power VKK: over -28V.

YES

Check

P7302 connection

condition and power F1+,

F2- both terminals: over 3.7V

Check power VKK: over

-28V Check 24 PIN:5.6V

YES

Check IC301

PT6324 power

50PIN VKK: -28V

9.51PIN +5V

NO

Refer to SMPS

Troubleshooting

Check P7302 assembly

YES

Check power

of each PIN

YES

OK

When 5V fails, check D301SR35 input and

output power

YES

NO

Replace the related part

Check IC100

--> IC301 DATA communication PIN PIN

75PIN-->3PIN STB

76PIN-->2PIN DO

78PIN-->1PIN

LGE Internal Use Only

YES

CLK

YES

NO

Check the

related part

YES

OK

IC100

75PIN - > STB

78PIN - > 1PIN CLK

Check Data output.

YES

76PIN--> DO

--> DATA input YES

Check the

related part

YES

OKOK

3-4

NO

Replace the related part

Replace the related partFLD light on?

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

5. PWM MODULATION PART

PWM modulation part

YES

Check P7905

9PIN 3.3V

YES

Check IC604 PS9829 VDD PIN power (3,10,22,29,39,47,56,65,

72,87,94) Check X601 2PIN 3.3V

YES

Check if

X601 12.288MHz is

working.

YES

Check IC604

PS9829 86PIN

CLK input

YES

Check

output of IC100

78KOKF2

21-->PWM_CLK 22-->PWM_DATA 43-->PWM_REST

NO

Refer to SMPS

Troubleshooting

Check the

related part of X601

YES

OK

Check R668(470Ω)

output

YES

OK

Check

resistance

output of LINE DATA:

R623 CLK: R624

RST: R619

NO

Replace the related part

YES

Check IC604

PS9829 DATA input

78 PIN-->DATA

79 PIN-->CLK

96 PIN-->REST

YES

Check PWM

MODULATOR

output FL:75(+)74(-)

FR:71(+)70(-)

YES

NO

YES

OK

Check

DVD ASS`Y PS9829

communication condition

(DVD INTERFACE)

YES

Check IC604

PS9829 DATA input

YES

OK

Check IC604 PS9829 part.OK

3-5

NO

Refer to DVD

Troubleshooting

Check resistance

output of each LINE

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

6. POWER AMP PART CHECK

Power AMP part check

YES

P7905 3PIN +

13, 14, 15PIN 21.5V

YES

Check input power IC700

34, 29, 26, 21PIN.

YES

Check input power of IC700,

1, 36, 17, 18, 19PIN +12V

YES

Check PWM MODULATOR

input 4, 6, 14, 16PIN

YES

Check POWER IC 700 34,

29, 27, 20PIN output.

NO

Refer to SMPS

Troubleshooting

Check resistance power

IC700: R702, 701, 726, 727, 724

Check output LINE COIL

LGE Internal Use Only

OK

YES

NO

3-6

Replace the related parts

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

7. PORTABLE FUNCTION

Portable function

YES

Check if JK305 contacts with

YES

Check IC200

(BU4052) 4, 11PIN input

waveform.

YES

Check IC200 (BU4052)

3, 13PIN output waveform.

YES

Check IC801

(MC4580) 2, 6PIN input

waveform.

YES

NO

Check IC200

(BU4052) 16PIN V

8PIN V

SS power.

Replace the related parts

Check IC801

(MC4580) 4PIN V

8PIN V

DD power.

Replace the related parts.OK

YES

DD

SS,

,

NO

Check u-COM (IC100)

3, 69PIN communication.

Refer to SMPS

Troubleshooting.

3-7

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

8. TV-AUDIO FUNCTION

TV-Audio function

YES

Check Video out

YES

Check Audio in

YES

Check IC200

(BU4052) 5, 14PIN

input waveform

YES

Check IC200

(BU4052) 3, 13PIN

output waveform

NO

Check SW4S1

Check IC200

(BU4052) 16PIN VDD

8PIN VSSpower

YES

Replace the related parts.

,

NO

Check u-COM

3, 6PIN communication

Check IC801

(MC4580) 2, 6PIN

waveform

OK

LGE Internal Use Only

YES

NO

Check IC801

(MC4580) 4PIN VSS,

8PIN VDD power

YES

Replace the related parts.

3-8

NO

Refer to SMPS

Troubleshooting.

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

9. TUNER FUNCTION CHECK

TUNER function check

YES

TUNER module (TUN800)

Check

is working.

YES

Check IC200

(BU4052) 1, 12PIN input

waveform.

YES

Check IC200 (BU4052)

3, 13PIN output waveform.

YES

Check IC801

(MC4580) 2, 6PIN input

waveform.

NO

Check TUNER MODUEL

power (Check 2PIN 9V)

Check IC200

(BU4052) 16PIN VDD,

8PIN VSS power

YES

Replace the related parts

Check IC801

(MC4580) 4PIN VSS,

8PIN VDD power

NO

Check u-COM (IC100)

3, 69PIN communication.

Refer to SMPS

Troubleshooting.

YES

OK

YES

Replace the related parts.

3-9

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

10. SMPS POWER TROUBLESHOOTING

No. 5.6VA

YES

Is the F101 Normal?

YES

Is the BD101Normal?

YES

Is the TH101 Normal?

YES

NO

Replace the F101 (Use the same Fuse)

Replace the BD101

Replace the R101

Is Vcc (9V ~ 18V) supplied to IC101

2PIN?

YES

IS the D959 normal?

YES

Is there about 2.5V at the IC103 1PIN?

YES

Is the IC102 normal?

YES

Is the D947 Normal?

YES

Is the D949 Normal?

YES

Is the D940 Normal?

NO

Is the D102 normal?

NO

Check or Replace the D102

Replace the D959

Replace the IC103

Replace the IC102

Replace the D947

Replace the D949

Replace the D940

Is the D943 Normal?

Is the D941 Normal?

Power Line of Main PCB is short

LGE Internal Use Only

YES

NO

3-10

Replace the D943

Replace the D941

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

No 5.0V

YES

Is the Vcc(5.6V)

supplied to IC957

1PIN?

YES

Is the IC957 4PIN “H”?

YES

Check or Replace the IC957

No 3.3V

YES

Is the Vcc(4.2V)

supplied to IC955

1PIN?

YES

Is the IC955 4PIN “H”?

NO

Check or Replace the D959

Check the CD CTL “H”

signal from µ-com

Check or Replace the D943

Check the P CTL “H”

signal from µ-com

YES

Check or Replace the IC955

No 12V

YES

Is the Vcc(13.5V) supplied to IC947

1PIN?

YES

Is the IC947 4PIN “H”?

YES

Check or Replace the IC947

NO

3-11

Check or Replace the D940

Check the P CTL “H”

signal from µ-com

LGE Internal Use Only

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

No -12V

YES

Is the voltage of

C932 -13V

YES

Is the IC155 2PIN

12V?

YES

Check or Replace the Q942

No VF+

YES

Is the ZD950

Normal?

YES

Replace the R993 or Q950, Q943

NO

Check or Replace the D970

Check the PWR CTL

“H” signal from µ-com

Replace the ZD950

LGE Internal Use Only

3-12

Only for training and service purposes

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

11. BLUETOOH PART (OPTIONAL PART)

Check bluetooth module

YES

Check IC200

(BU4052) 2, 15PIN input

waveform.

YES

Check IC200 (BU4052)

3, 13PIN output waveform.

YES

Check IC801

(MC4580) 2, 6PIN input

waveform.

YES

NO

Check IC200

(BU4052) 16PIN V

8PIN V

SS

Replace the related parts

Check IC801

(MC4580) 4PIN V

8PIN V

DD power

Replace the related parts.

power

YES

DD

SS,

,

NO

Check u-COM (IC100)

3, 69PIN communication.

Refer to SMPS

Troubleshooting.

OK

3-13

LGE Internal Use Only